Mods to improve Euro fuel consumption

[6MT]

Hi,

Wanted to know if anyone done any mods to their Euro to improve fuel consumptions?

Mine (manual) runs 9.5 - 10.5 L/100km. This might not be too bad for medium size car, but as fuel price is getting dearer, this might create a pinch.... :(

my friend even suggested to convert my car to run on LPG, any of you guys have done this?... any advice or comment?

Thanks

[aaronng]

LPG will give you higher fuel consumption. The only advantage is that LPG is cheaper.

The best mod is to use proper tyre pressure of about 34psi if you have the stock 16" tyres. Also, service your car regularly, use a 5w-30 or 10w-30 oil, make sure your air filter is clean and most of all, NO TRAFFIC LIGHT DRAGS.

[yfin]

Don't even think about running the Euro on lpg. Honda never designed the car to run on LPG. You will lose your boot and Honda will not want to know you should have have any warranty issues with the engine.

[henri123]

Does improved air intake increase fuel consumption?

My family friend put in this 'direct intake' if thats what you call it, on my euro and i can get up to about 550 - 600 km each tank before refilling driving with 6th a lot.

Just a thought ^^

[iversonruls]

u know wat? just sell ur car and get a jazz if u want lower consumption
to be honest 9.5 - 10.5 is not that high for the euro

[tanalasta]

You're better off doing things like:
1. Pump your tyres to 35PSI or at least above the recommend pressures of 32 front and 30 rear (for 17")
2. Use Premium Unleaded (BP Ultimate being my preference) although the extra fuel consumption does not justify the increased premium. It's not cost-effective but it's good fuel.
3. Use decent engine oil. Motul 8100 fully synthetic or Mobil Gold.
4. Simple things like using the cruise control and accelerating gently (or avoid accelerating at all). A steady foot on the pedal helps!

[10KRPM]

Basically drive only up to 2-2500rpm....no air con. Take out any excess stuff in the car....shoes, bags, umbrellas etc etc

That might save you ...... half a litre?

Probably the best one is....dont drive the car if you know your going to be stuck in peak hour traffic.

[aaronng]

Does improved air intake increase fuel consumption?

My family friend put in this 'direct intake' if thats what you call it, on my euro and i can get up to about 550 - 600 km each tank before refilling driving with 6th a lot.

Just a thought ^^

Freer flowing intake = more air.
More air = more fuel
More fuel = higher fuel consumption.

Your family friend probably has a lighter foot.

[LXRY]

No real mods you can do...........as above ^^^


9.5-10.5 is very, very good for the weight of the car IMO it's excellant !! I run my car on mobil synergy 8000 costs me a bit more but I get the same klm's as I would normal premium unleaded......more efficient, better response, less effort to go from a to b IMO anyway.

[r-r-redEuro]

yeah, appreciate that your running 9.5 - 10's man. im doing 14's = =" and only get 400 - 480kms average per FULL tank.

[6MT]

Looks like LPG is out of the question then .....

been asking few converters and told that no approved kit is available for the euro, and only couple of fitters told me they can do it, but I am not so convinced...the way they explain the fitting and the parts looks kind of dodgy

asked Honda last time they did not recommend LPG installation either

my tyre pressures are already around 34-35psi, and I shift up usually not more than 3000rpm
I always drive to work during peak city traffic... so not much choice on this
guess I will just remember to use 5-30 W oil on next service

Thanks for the feedback guys....

[r-r-redEuro]

where do you work ? drive to the nearest station of some sort and train it from there. some people on ozhonda does that, and around my area alot of people do that.

[6MT]

Btw I live in WA,
public transport is not as good here ....
prefer to keep driving my car ... :angel:

[aaronng]

Peak city traffic in WA can't be as bad as city traffic in Melb or Sydney. :)

If you want lower fuel consumption, get a Jazz GLi. That thing literally runs on air!

[my_vtec77]

I put fuel saver or something from Dealer last time when i did service. Cost about 200. I think it just a rip off from Honda. I never check my fuel consumption though.

Hi aarong, is it safe to use 34psi? coz they recommand 32psi. How much max safe psi can we go? Will it depend on hot or cold weather?

[aaronng]

For the Dunlops, I think max is about 45-50psi. Depends on the tyres. My current tyres has a max of 51psi. I just use 34-36psi.

[Ozluder]

dude, I get 560kms when the fuel light comes on and get it upto 600kms when the fuel needle is close to the redline.

9.5l / 100km is quite good for a 2.4litre engine. My mums 1.8litre corolla does the same. Just for some background. My euro is an 03 base model auto. 106,000kms clocked up and I use shell 98 octane fuel. I'm always driving in traffic to and from work stopping and starting all the time. So i'm really happy with the fuel consumption i'm getting. :D

[aaronng]

I spent the last week house hunting and in the traffic jam of peak hour Sydney traffic, I still got 10.5L/100km. It's slightly better here in Melb at 10L/100km. Best is when I am on the freeway, 7.1L/100km.

[hotout]

quickest way to increase fuel consumption on virtually any car is to leave the spare tire at home....it's so heavy...if you have a flat just get a mate to bring your spare over. I get a flat once every maybe 4 years?

Your Euro has tyre deflectors in the front, dunno how much effect tyre deflectors for the rear tyres will have??

[clayton4115]

get a Prius! (toyota) at 3l/100kms in peak hour traffic you can't beat that!!!

[BusterSonic12]

close all the windows

[power_of_dreams]

LPG will give you higher fuel consumption. The only advantage is that LPG is cheaper.

The best mod is to use proper tyre pressure of about 34psi if you have the stock 16" tyres. Also, service your car regularly, use a 5w-30 or 10w-30 oil, make sure your air filter is clean and most of all, NO TRAFFIC LIGHT DRAGS.

34psi all around or 34 upfront and 32 rear?

[aaronng]

34psi all around or 34 upfront and 32 rear?

All round. If you find that it is still comfy, you can increase it to 35 or 36psi all round. Not much point going higher than 36psi unless your tyres are "special".

[Euro76]

I'm now enjoying holiday in Indo...no Euro's here but lots of Jazz, City (hideous design!), Elypsion (bigger than Odyssey, very nice but did not make its way to Australia), new American Accord will sell here soon.

Anyway to the topic, from my experience driving Euro,\ I can see ways to save fuel but previous posters here have suggested before.

- If your Euro has 6MT, then it's good...manual transmission always save more fuel than the automatic.

- Don't turn on A/C, use only when it's necessary ie. when you feel hot inside the car. When the car gets cooler and you feel comfortable then turn A/C off. I don't use A/C quite often. Just open the window during driving.

- If it's rain, close the windows and don't turn on A/C if possible (except if it's hot weather). Switch on button to let the outside air go inside cabin.

- Of course Premium Unleaded always be recommended, I always use Shell Optimax but my bro in law always suggested BP Ultimate / Mobil 9500 (if I'm not mistaken) is much better. Can anyone confirm this? Why better?

- When filling the fuel, when the pump stops to indicate full tank I normally go little bit more. Although the pump stops repeatedly, I also repeatedly press the trigger. Use your feeling and judgment carefully to make sure the fuel does not spill out. If you can do it, it will give your Euro extra more kilometres to travel.

- Don't accelerate the car beyond 3,000rpm. I have problem with keeping accelerating, my normal acceleration from standing start 1st-2nd gear 3,000-4,000rpm. Euro lacks torque below 3,000rpm. Sometimes I am naughty that I fully accelerated, occassionally hit the rev limiter. This does not sound too good but I feel VTEC kicking is glorious :D

- Under normal driving condition, I use 5th gear on 50-60km/h range, the rev shows 1,800 rpm at 60km/h which is good. I use 6th gear from 70km/h onwards.

If I can keep all the above, my Euro can travel 600-660km on a tank of fuel :cool: :thumbsup:

[aaronng]

- Don't turn on A/C, use only when it's necessary ie. when you feel hot inside the car. When the car gets cooler and you feel comfortable then turn A/C off. I don't use A/C quite often. Just open the window during driving.

Leave it on auto and the A/C will turn on and off on its own. If you are on the freeway, driving with the windows up means less drag and better fuel consumption. You're better off driving with the windows closed and climate control on.



- When filling the fuel, when the pump stops to indicate full tank I normally go little bit more. Although the pump stops repeatedly, I also repeatedly press the trigger. Use your feeling and judgment carefully to make sure the fuel does not spill out. If you can do it, it will give your Euro extra more kilometres to travel.
No point doing this. You are trying to get good fuel consumption, not maximum range. Also, any overfill will just spill out through the overflow hole to the bottom of your car.



- Under normal driving condition, I use 5th gear on 50-60km/h range, the rev shows 1,800 rpm at 60km/h which is good. I use 6th gear from 70km/h onwards.
Using more throttle at low RPM uses more fuel. If you are going uphill, you use more fuel at 1800rpm in 5th gear at 50km/h than using 4th gear instead. Don't lug your engine.

[yfin]

Some good suggestions though I would go crazy not revving the Euro past 3000rpm. Somethings are more important (like driving enjoyment) than saving a buck or two of fuel each week.

I also probably wouldnt do what you are doing in terms of gear selection (5th gear at 50kph). The engine might not sound like it is lugging but in my view it is a poor gear choice for that speed and you are doing harm to the longevity of the vehicle with that gear selection to just save a few pennies in fuel.

[2fast2furious]

u know wat? just sell ur car and get a jazz if u want lower consumption
to be honest 9.5 - 10.5 is not that high for the euro

Not very helpful are you boy, is the answer to all the fuel saving questions in the world buy a honda jazz? The guy wants to save fuel in his Euro.

lighter accelerations and lighter braking, avoid congested roads, air con off. That should make quite a big difference.

[tron07]

Some good suggestions though I would go crazy not revving the Euro past 3000rpm. Somethings are more important (like driving enjoyment) than saving a buck or two of fuel each week.

I also probably wouldnt do what you are doing in terms of gear selection (5th gear at 50kph). The engine might not sound like it is lugging but in my view it is a poor gear choice for that speed and you are doing harm to the longevity of the vehicle with that gear selection to just save a few pennies in fuel.

I do let the car cruise or roll on 5th gear at 50-60 by itself and no throttle during that time.... minimal or no fuel is being injected thus safe fuel, and drop a gear or two when I want to accelarate or blip the gas pedals.

[aaronng]

I do let the car cruise or roll on 5th gear at 50-60 by itself and no throttle during that time.... minimal or no fuel is being injected thus safe fuel, and drop a gear or two when I want to accelarate or blip the gas pedals.

With little to no throttle is fine. I think the limit where the engine stops injecting fuel is 1500rpm. Go below that and the engine starts putting fuel in again.

[EuroAccord13]

Another note is not to leave the car in neutral when you are in motion or going downhill, that consumes petrol as it kicks the injectors in....

[cupnoodle]

So engine braking is not only good for your brake pads, it's good for your fuel consumption too. Nice!

[henri123]

Another note is not to leave the car in neutral when you are in motion or going downhill, that consumes petrol as it kicks the injectors in....

hahah dam i'm always thinking i'm saving fuel when going down hill and stick it in neutral and just ride the brakes. dam.

[Encor3]

light weight wheels i dont think anyone has said it. but Cutting down the weight will help with fuel consumption as it wouldn't need as much to move the car.

Lighter the better.

[clayton4115]

i drive a civic and i have inflated my tyres to 45psi, all of them.

[luxobarge]

As said light wheels are great... weight reduction is always going to be a good thing (acceleration, braking, handling) but its even better when you reduce unsprung mass or in this case rotating mass (ie wheels). I remember reading somewhere reducing unsprung mass in equivelant to 4 times that amount sprung (ie 1kg unsprung = 4kgs sprung).

clayton4115: whilst i could understand running 45psi on the track... dont you think its a bit overboard for street?

[Encor3]

i drive a civic and i have inflated my tyres to 45psi, all of them.

45psi. thats quite high, i think 40 psi is enough,
having such high tyre pressure wouldn't help with high speeds and also your rear tyres should be lower than your fronts
Having good tyre pressure really makes a big difference on fuel consumption.

[shadou]

45 psi!!! why not go the extra 5 psi? overkill with the air mate

[tanalasta]

I too think 45PSI is overboard. In hot weather, this may be dangerously high.

You'd wear the centre of your tyres down unnecessarily as well as have a detrimental effect on grip, ride and handling.

For 17" Potenza's or C-drives I found 36PSI was more than enough.

[tony1234]

Agreed.No more than 40psi.38 seems to be a good compromise between firmness(and improving fuel economy)and ride quality.

[clayton4115]

yea well i am trying to get good fuel economy, i suppose overinflated better than underinflated !

[aaronng]

yea well i am trying to get good fuel economy, i suppose overinflated better than underinflated !

Between 40 and 45, you probably get very little gains. The biggest difference is around the 30psi area. I run 36psi.

[clayton4115]

yea ive got mine to 40 now !

:p

[one4spl]

I got new Goodyear F1 DS G3s fited to my Euro about 10 minutes after picking it up from the previous owner.... and they are very noisy, so I went back to the shop and they put 42PSI (almost 300kPa) into them... they are a bit quieter, and still well short of the max 350kPa printed on the side.

I dont think steel belted tyres really change shape with pressure, the old "wearing in the middle" thing is an olds wives tale from the cross-ply days. It's just shifting the ride/grip/noise ratios.

[shadou]

No more than 38psi for any normal family sedan for me, even I use 36/34 psi on my moms avalon and that weighs around 15xx kg

[aaronng]

I dont think steel belted tyres really change shape with pressure, the old "wearing in the middle" thing is an olds wives tale from the cross-ply days. It's just shifting the ride/grip/noise ratios.

The wear in the middle still happens though when the tyre is overinflated though...

[phobolism]

So engine braking is not only good for your brake pads, it's good for your fuel consumption too. Nice!

your being sarcastic about the fuel consumption part right??

[aaronng]

your being sarcastic about the fuel consumption part right??

If you stay above 1500rpm while engine braking, the ECU shuts the injectors off. Of course, you'll spend fuel blipping the throttle to revmatch as you downshift.

[one4spl]

We have just done the first complete tank-full in our Auto 05 Lux and got 8.5l/100km. IMHO, thats a fantastic result for a mixture of highway and CBD driving. The Prius I used to get from the QLD govt car pool only got 5.4l/100km on average.

Bring on the Euro Diesel!! (in Auto, unlike the Mazda Diesel, please.).

[Merlin086]

Tyres have to run at ideal pressure to get ideal tyre wear.

Anything else is a compromise between tyre wear and fuel consumption.

It is false economy to overinflate tyres for the benefit of fuel economy at the sacrifice of tyre wear.

That having been said, the question to be asked is WHAT is the ideal pressure for each model of tyre for for each car?

Personally I have been running nitrogen in my euro since new,1 yr, with a front pressure of 37psi and rear 35psi.
My re040's are nearing the end of their life, with almost 30k on them.
The edges are worn, despite having at least 10k left across 90% of the tyre.

I hate to think of how feathered the edges would be had I run at the recommended pressure .....or is this a common problem with the re040's?

[Pumped]

lol anyone got hints of how to get your valve caps off if there on so tight that when you twist them it twists the whole valve?

[Merlin086]

lol anyone got hints of how to get your valve caps off if there on so tight that when you twist them it twists the whole valve?

Can't you just grab the valve stem with a pair of plyers and unscrew the cap?

If you have sleeves on the valve stems like mine, you make be able to push the sleeve down a bit and fit a pair of side cutter jaws between the sleeve and cap to grip the thread. My caps don't quite bottom out on the sleeves, leaving a slight gap where I can see the stem thread.

Screwed them on too tight eh.....:thumbdwn:

[Pumped]

:( yea ive got sleeves on them so if i try and hold them with plyers they spin, ill have to fiddle around with it!

Caught kids trying to steal my caps one day and i did them up as tight as i could by hand hadnt tried them for a while, went to check the pressure and now there stuck!

ill try squashing the sleeve around the valve and trying to get them undone

[phobolism]

If you stay above 1500rpm while engine braking, the ECU shuts the injectors off. Of course, you'll spend fuel blipping the throttle to revmatch as you downshift.

so aslong as u stay over 1500rpm without blippin throttle injectors wont engage, which means clutches will be worn more then right? so really cant really escape, save one thing, wear another...someone correct me if im not seein the full pic

[JohnL]

Hi,

Wanted to know if anyone done any mods to their Euro to improve fuel consumptions?

Mine (manual) runs 9.5 - 10.5 L/100km. This might not be too bad for medium size car, but as fuel price is getting dearer, this might create a pinch.... :(

my friend even suggested to convert my car to run on LPG, any of you guys have done this?... any advice or comment?

Thanks

Get a CB7, mine gets 6.4L to 6.7L per 100km on the highway, very happy with that (especially for a car getting very close to 250,000km on the clock!, uses no oil either!!).

On the other hand, the f22A9 motor only has around 150hp, which I'm less happy about!

[JohnL]

Does improved air intake increase fuel consumption?

My family friend put in this 'direct intake' if thats what you call it, on my euro and i can get up to about 550 - 600 km each tank before refilling driving with 6th a lot.

Just a thought ^^

There is supposedly a correlation between ambient air temp and fuel consumption, with lower air temp giving better consumption (this is supposedly at least one reason why truckies like to drive at night, i.e. better fuel consumption from cooler air).

If this is correct then if the "direct intake" is a cold air intake it might benefit consumtion slightly. if on the other hand it's a 'short ram' drawing hot air from inside the engine bay it might make consumption slightly worse. One thing is for certain, hot air is damaging for power production, not greatly, but...

[JohnL]

Freer flowing intake = more air.
More air = more fuel
More fuel = higher fuel consumption.

True, but only at wider throttle openings, not an issue when you not actually using the higher airflow potential.



Your family friend probably has a lighter foot.

More help than anything else, other than proper maintenance!

[JohnL]

I too think 45PSI is overboard. In hot weather, this may be dangerously high.

You'd wear the centre of your tyres down unnecessarily as well as have a detrimental effect on grip, ride and handling.

If the max reccomended pressure on the sidewall is 51psi then 45 isn't 'unsafe'. It probably isn't actually unsafe even if the max pressure is only 44psi, but as a rule it's probably unwise to exceed the reccomended max (tyre manufacturer's reccomended, not car's).

The max reccomended psi is a cold setting, if the psi goes over this when the tyre is warmed up then this is OK, the tyre manufacturers take this into account when setting their max reccomended psi. The 'burst' pressure for any tyre will be way higher than the reccomended max, well over 100psi. The trye will most likely generate less heat at higher psi because there is less rolling distortion of the tyre casing (which is also why higher psi gives better fuel consumption), so pressure rise over cold psi will probably be less than at lower psi. There are of course points of dimishing return.

Centre tread wear may or may not be an issue depending on the tyre, you'd need to keep an eye on it. More of an issue with cross-ply than radial. If you run much neg camber with high psi then you may wear the inner edge / half of the tread more than with lower psi because there will be less compliance in the sidewall at higher psi and thus you'll have more weight on the inner part of the tread and less on the outer part.

Grip and handling may suffer with high psi, but may improve, depends on the tyre and what the benchmark psi might be. Ride (harshness) will suffer with higher psi.

[aaronng]

so aslong as u stay over 1500rpm without blippin throttle injectors wont engage, which means clutches will be worn more then right? so really cant really escape, save one thing, wear another...someone correct me if im not seein the full pic

I'm don't condone downshifting without revmatching... :) But yeah, if they like to downshift without revmatching, they are wearing their clutch and will end up spending more money on a clutch replacement.

[Blitzen]

Hi,

Wanted to know if anyone done any mods to their Euro to improve fuel consumptions?

throtle restrictor, floor it - there's nothing ;)

change your driving style - smooth it out, short shift

avoid stop go traffic

tailgate - eat their slip stream

cane it through corners - use maximum velocity without engine power to propel the car as far as you can before using the throttle

[JohnL]

tailgate - eat their slip stream

Death wish?!


cane it through corners - use maximum velocity without engine power to propel the car as far as you can before using the throttle

Probably one of the most entertaining ways to save money on fuel. This is possibly something that we male drivers could tell the girlfriend or wife?! ("yes darling, I really do need to drive that fast through corners, don't you know it saves petrol, and petrol is so expensive..."). An air of automotive superiority will help us sell the idea to them, maybe.

Girlfriends or wives, being women, and therefore much more sensible than most men, will most likely instantly spot the fatal flaw in this argument, that being the significantly increased amount of money we will spend on tyres as a result of our 'economy' drive.

Bugger, next idea!!

[6MT]

Get a CB7, mine gets 6.4L to 6.7L per 100km on the highway, very happy with that (especially for a car getting very close to 250,000km on the clock!, uses no oil either!!).

On the other hand, the f22A9 motor only has around 150hp, which I'm less happy about!

CB7? is that Accord Euro R motor? if it is, wouldn't installing a new motor take lots of kms of driving before I can start to get a saving in fuel (dollar wise)

[JohnL]

CB7? is that Accord Euro R motor? if it is, wouldn't installing a new motor take lots of kms of driving before I can start to get a saving in fuel (dollar wise)

I so wish it were an Accord Euro R motor!!! New motor? No, not even close! This engine has nearly 250,000kms on it (and in great shape, still going strong!). CB7 is the model designation for the early 90s incarnation of the Accord. It was a flippant remark, sorry to confuse!

[TheGoodDeal]

Just fill 1/2 tank of fuel for short trips to reduce the weight.

[JohnL]

Just fill 1/2 tank of fuel for short trips to reduce the weight.

Will help to some degree in city driving where you spend a lot of time acceleraring up to speed, slowing down again, accelerating, slowing, accelerating...

In town you can refuse to ever carry passengers (tell them they're too fat, but be polite!), which means you can save even more weight by taking all the unneeded seats outs! Will make almost no difference on the highway where you spend a lot less time moving your mass from low to higher speed, but instead are maintaining a fairly constant speed for long periods.

On the open road you're enemies are aerodynamic drag and rolling resistance. To lessen rolling resistance you can pump up the tyres, and align the wheels to zero toe front and rear.

Not much you can do with aero, but you can get rid any roof racks which do generate drag (even those 'aerodynamic' ski racks). If you have a rear 'wing' or 'spoiler', then you could ditch that too, many road car wings etc actually increase drag but do nothing to lessen it (or decrease lift, let alone generate any downforce, they are only cosmetic!). A front air dam may help slightly (very slightly) because it lessens flow under the car, which is aerodynamically 'unclean' and generates very 'dirty' air. Don't use the radio aerial...

I find that cleaning the car makes it perform better and even handle better, so might improve economy. Some people might say this is in my head, and I know they'd be right!

[simonnowis]

yeh, tyre pressure, good oil.
i also heard intake, more airflow so more efficient fuel burn.
theres also like fuel saver clip things, ebay has them. a friend bought it and put it on his 2003 lancer, he told me he did notice a slight better fuel economy.
anyone else tried them before?

[johnprocter]

lol they look like a waste of money

[Merlin086]

Get a CB7, mine gets 6.4L to 6.7L per 100km on the highway, very happy with that (especially for a car getting very close to 250,000km on the clock!, uses no oil either!!).

On the other hand, the f22A9 motor only has around 150hp, which I'm less happy about!

I frequently got 6.5L/100k's in my euro lux ( now about 1460kg with jtune exhaust)

and I expect to get about the same on a trip with the xtreme package, and that's more power than a CL7 - Euro typeR


That 6th gear makes all the difference!

[JohnL]

i also heard intake, more airflow so more efficient fuel burn.

At low throttle openings the standard somewhat strangled induction system will flow quite well enough, not constricted enough to affect efficiency at smaller throttle openings.

At wider throttle openings a more constricted induction tract (upstream of the butterfly) may mean that you have to open the throttle butterfly slghtly wider to allow X airflow than with a less constricted induction, which might mean that with less constriction upstream the throttle position sensor tells the ECU to flow less fuel despite more air passing through the throttle body, i.e. with less constriction the throttle butterfly will be a little less open than with a higher induction restriction, so the ECU 'thinks' a bit less air is being passed, thus injects a little less fuel (though the MAP sensor may contradict the throttle position sensor to some degree).

Considering that Hondas seem to run on the rich side at wider throttle openings, this might make a slight improvement to economy because the engine runs a little leaner, but only slight.


theres also like fuel saver clip things, ebay has them. a friend bought it and put it on his 2003 lancer, he told me he did notice a slight better fuel economy.
anyone else tried them before?

I can't believe anybody still buys that junk, they are well known (and have been tested) to do absolutely zip, a ripoff. Your freind is either imagining the improvement, or since fitting it has become more consciuos of economy and unconciously lightened his foot...

You could try an 'Energy Polariser', probably works at least as well (ask Peter Brock about them). If we want more money, maybe we could accept deposits into our accounts from a Nigerian prince?!

[Merlin086]

You could try an 'Energy Polariser', probably works at least as well (ask Peter Brock about them). If we want more money, maybe we could accept deposits into our accounts from a Nigerian prince?!

I save heaps of petrol by astral travelling......:thumbsup:

....really fast too....and no cops!......

More likely than those gimmicks doing anything beneficial.....

[JohnL]

I save heaps of petrol by astral travelling......:thumbsup:

....really fast too....and no cops!......

More likely than those gimmicks doing anything beneficial.....

Pesonally, I swear by the rock crystal hanging off the mirror (where the fluffy dice used to be), it gives out a cosmic aura that aligns the fuel molecules in the direction the car is travelling in, so the car can go further on less because the fuel isn't 'fighting' against the flow (makes sense to me!).

[Blitzen]

Death wish?!



Probably one of the most entertaining ways to save money on fuel. This is possibly something that we male drivers could tell the girlfriend or wife?! ("yes darling, I really do need to drive that fast through corners, don't you know it saves petrol, and petrol is so expensive..."). An air of automotive superiority will help us sell the idea to them, maybe.

Girlfriends or wives, being women, and therefore much more sensible than most men, will most likely instantly spot the fatal flaw in this argument, that being the significantly increased amount of money we will spend on tyres as a result of our 'economy' drive.

Bugger, next idea!!

dude you write too much, anyway, have we talked about the whats in the tyres? instead of air :) ---> Nitrogen! <---

I'm not joking, airplanes use them in their tyres as well, operates at lower temperature, looses pressure at slower rates than air, bit expensive though

[Merlin086]

dude you write too much, anyway, have we talked about the whats in the tyres? instead of air :) ---> Nitrogen! <---

I'm not joking, airplanes use them in their tyres as well, operates at lower temperature, looses pressure at slower rates than air, bit expensive though


Expensive? .....at $6/tyre or $5 for a bike tyre.....

Best value I can think off.....at $1000+ for 4 performance it represents great value for $24 or 2.4% extra with a possible tyre life improvement of up to
25%, even @ 10% improvement your way in front.

[tony1234]

Expensive? .....at $6/tyre or $5 for a bike tyre.....

Best value I can think off.....at $1000+ for 4 performance it represents great value for $24 or 2.4% extra with a possible tyre life improvement of up to
25%, even @ 10% improvement your way in front.
Me too.$5/tyre at Bob Jane,free topups,don't have to check tyre pressure for 2-3 mths.:thumbsup:

[JohnL]

dude you write too much,

You may be right, but it's more entertaining than 99&#37; of what's on the box (especially this time of year!). Probably should get a good book!


anyway, have we talked about the whats in the tyres? instead of air :) ---> Nitrogen! <---

I'm not joking, airplanes use them in their tyres as well, operates at lower temperature, looses pressure at slower rates than air, bit expensive though

Just because planes and some race teams use nitrogen don't think this means it's worth using for you and me. No real performance gain here (nor fuel consumption gain), especially for a road car. Nitrogen makes up 78% of the air we breathe or put in our tyres, so when we use air it's mostly nitrogen anyway. It doesn't leak out of the tyre any more slowly than air does. It doesn't "operate at lower temperature" (at least not in any direct manner). And it is more expensive than air which is free!

The reason why nitrogen is used in racing tyres (some) is that bottled nitrogen is dry, i.e. it contains no moisture. You could use quite a number of different bottled gasses for this reason, but nitrogen is the cheapest and very inert (doesn't react with chemicals in the rubber, but not to any significant degree less than ordinary air, the oxygen content of which would be the most reactive).

If you use air then because air has moisture content you end up with some water inside the tyre. This can condense into actual liquid water, and when the tyre warms up it turns into gas, and as it does so the water increases it's volume substantially which in turn can significantly increases the psi in the tyre.

This is not usually enough to be an issue for a road car tyre, but can be for a racing tyre where only a few psi can make a difference to tyre performance and introduces an inconsistency that would otherwise have to be accounted for. All gasses do increase volume when warmed, and this increases the psi in a tyre cold vs warm, but all gasses do this to the same degree and to a much lesser degree than a liquid turning to a gas. A tyre filled with dry gas (i.e. nitrogen) will gain less pressure with temp rise than will a tyre filled with humid / moist air, and with dry gas this pressure rise will be consistent with temp gain, but with moist air will be inconsistent depending on moisture content.

The only reason why nitrogen is used is because it's dry, and since it has no water content then there is no gassification of the water to affect the degree to which psi increases as the tyre gets warm, i.e pressure rise due to otherwise variable water content is eliminated and thus pressure rise due to warming of the gas inside the tyre is more predictable and consistent. This the only reason why nitrogen is used, it has no special properties for use in tyres other than being dry.

There is no gain to be had relative to fuel consumption, none whatsoever! (if anything you could mount an argument that humid air will improve economy over dry nitrogen because it gains more psi in the tyre when it gets hot, so you get less rolling resistance!). If you are using nitrogen then you are just wasting money (maybe not a lot), unless you are a racing your car a pretty high level of competition...

Claims of any tyre life improvemnt are not credible, let alone a claim of a 25% improvement!

[Merlin086]

Quote^

Claims of any tyre life improvemnt are not credible, let alone a claim of a 25% improvement!

I did say "possible tyre life improvement"

It is a well known fact that pressure affects wear rate of tyres.

I prefer to decide on my tyres' operating pressure instead of leaving it up to the prevailing weather, with a possible 10 psi increase.

I often hear the one "why use nitrogen when air is 78% nitrogen", but that argument is about as lame as drinking sewerage 'cause it's 95% water.

Each to their own...........:thumbsup:

[BiLL|z0r]

I often hear the one "why use nitrogen when air is 78% nitrogen", but that argument is about as lame as drinking sewerage 'cause it's 95% water.

HAHAHAHA, tooshay.

[johnprocter]

Quote^

Claims of any tyre life improvemnt are not credible, let alone a claim of a 25% improvement!

I did say "possible tyre life improvement"

It is a well known fact that pressure affects wear rate of tyres.

I prefer to decide on my tyres' operating pressure instead of leaving it up to the prevailing weather, with a possible 10 psi increase.

I often hear the one "why use nitrogen when air is 78% nitrogen", but that argument is about as lame as drinking sewerage 'cause it's 95% water.

Each to their own...........:thumbsup:
ooo snap ;)

[Suntzu]

The best mod to improve fuel consumption is to put a 2 inch block behind the accelerator so you only get 60&#37; throttle. Cheap and very effective.

[JohnL]

I did say "possible tyre life improvement"
It is a well known fact that pressure affects wear rate of tyres.
I prefer to decide on my tyres' operating pressure instead of leaving it up to the prevailing weather, with a possible 10 psi increase.


I see I'm going to have to argue my point!

You said "possible tyre life improvement", and I will modify my previous statement to say 'any improvement worth having is higly improbable'.

It's not impossible for there to be some very slight wear improvement from less pressure build up with nitrogen, assuming your cold psi with nitrogen is at, near or over the optimum for minimum wear. On the other hand any pressure rise could be beneficial for wear if the initial psi is too low for minimum wear. The affect is likely to be slight, as is the probable additional psi increase with ordinary moist air.

A 10 psi increase with ordinary air is I think very unlikely, but I can't say that it's utterly impossible (most I've noticed on any of my cars is about 5psi increase after a long run on a hot day). From my karting days (using air to inflate tyres, and keeping in mind the temps on racing tyres will be much higher than is likely to be seen with tyres on the road), I'd expect to see a psi rise cold to hot of anywhere bewteen 3 to 5psi depending on track and ambient temps, and perhaps how much moisture happened to be in the tyres on the day.

I've been told by the few karters I knew who were using nitrogen that they'd get a consistent 2 or 3psi increase depending on track and ambient temps (and I was competetive with these people, they weren't gaining any obvious advantage from using nitrogen).



I often hear the one "why use nitrogen when air is 78&#37; nitrogen", but that argument is about as lame as drinking sewerage 'cause it's 95% water.
Each to their own...........:thumbsup:

The other gasses in the air (other than nitrogen) make no difference, they expand with temp at the same rate as the nitrogen does. It's only the unknown % (but relatively tiny amount ) of liquid water that is of concern.

QUOTE=Merlin086;1465831]
Expensive? .....at $6/tyre or $5 for a bike tyre.....
[/QUOTE]

Sounds a lot to me, sharp business practice I'd say! The nitrogen they're putting in your tyres would cost a fraction of the $6 they're charging you, more like $0.06c I'd think.

AND, have you watched them fit the tyres? Do they do the initial inflation / bead seating with compressor hose? If so then you could easily have moisture in the tyre from this source, unless they use a very good de-humidifier in the line (but few places do and no line de-humidifier is 100% effective). Keep in mind that the air that comes out of a compressor is often much moister than ambient humidity. Do they use a water based lubricant like water and soap or similar? If so then you're doubly ripped off because the lube they're using is introducing far more water into the interior of the tyre than the humid compressed air ever could.

Once moisture is inside the tyre, the tyre has to be deflated and inflated numerous times using dry gas, this will purge the moisture but it takes a fair few repeated inflation / deflation cycles to do it properly (and even then...?). Does Bob Jane do this? The only way to mount tyres without introducing moisture is to dry mount them, or to use a non water based lube such as 'rubber grease' or similar.

I can guarantee you that F1 teams (etc) never allow water near their tyres until after they're fully mounted on the rims. And yes, I'll bet they do use nitrogen not only to inflate, but also to seat the bead, but this doesn't mean it's remotely necessary or noticably advantageous for a road car, even a fast one...

[JohnL]

Me too.$5/tyre at Bob Jane,free topups,don't have to check tyre pressure for 2-3 mths.:thumbsup:

Why not? Makes absolutely no difference what gas is inside the tyre, it will still leak if it has a leak. Not checking the pressures for any extended period is asking for trouble, no matter what gas or mixture of gasses may be inside the tyre.

[Merlin086]

We'll have to agree to disagree.....

But honestly, there is a lot of contradictions and ignorance in your posts.

If the air coming out my compressor is moister than the ambient air, why do I have to drain my compressor through all seasons.?

You are relating go-karts rising 2-3psi due to track temperature, with a fraction of the volume of air that a car tyre has. And the reason for using nitrogen you are relating to expecting better performance,but only in regard to possibly having the incorrect pressure in the first place.

Tony1234 is referring to the ability of air to seep through the rubber, and not in the event of a puncture or leaky valve.

I was a sceptic like you, but the more knowledge I gained, the more I found that I have the ability to make my own judgement.
IMHO it is a economical investment, and a very small price to pay for the possible benefits.

Try reading this..
http://ezinearticles.com/?Selling-Nitrogen-In-Tires---Is-It-All-A-Lot-Of-Hot-Air?&id=38142

[Suntzu]

Im getting that rechargeable 18v handheld air compressor from aldis today for $39.95. Never have to line up at caltex again.

[eurofan]

Im getting that rechargeable 18v handheld air compressor from aldis today for $39.95. Never have to line up at caltex again.

sounds like a great idea, i was contemplating getting a pump as well. would make it so much easier to assess how different tyre pressures affect driving feel. can you post some comments on the pump after you've had a chance to test it out? :thumbsup:

[tron07]

My friend keep a air compressor and remove the full size spare.... save more weight.

[tony1234]

Why not? Makes absolutely no difference what gas is inside the tyre, it will still leak if it has a leak. Not checking the pressures for any extended period is asking for trouble, no matter what gas or mixture of gasses may be inside the tyre.
Well i'm telling you for a fact that i get 1-2psi loss over a 2-3 mth.period.(i've been using Nitrogen for approx.8 years)With just air in my tyres i used to lose more than 1-2 psi over the same period.I run 40psi all round.If you have a leak of course it doesn't matter what gas/gasses are in the tyre:rolleyes:

[JohnL]

[QUOTE=Merlin086;1467352]We'll have to agree to disagree.....
But honestly, there is a lot of contradictions and ignorance in your posts. [QUOTE]

Now now, be nice!

[QUOTE=Merlin086;1467352]
If the air coming out my compressor is moister than the ambient air, why do I have to drain my compressor through all seasons.? [QUOTE]

Dehumidifiers are fitted (when fitted) to compressors for good reason. At some times the air coming from the compressor may be drier than ambient, at others it may be higher, sometimes a lot higher. If a lot of water is allowed to build up then at times liquid water may be 'picked up' and expelled as water droplets, not just moisture in the air.

Water will tend to build up (condense) inside the compressor tank when the tank is cold (colder than the air going into it), likely especialy on humid mornings. Moisture may then be expelled as the tank temperature rises during the day. When this occurs the air exiting the hose can easily be higher than current ambient humidity.

[QUOTE=Merlin086;1467352]You are relating go-karts rising 2-3psi due to track temperature, [QUOTE]

No, not due to track temp, due to the temperature rise of the gas inside the tyre, which is primarily caused by the rise in tread temp caused by surface friction and by tyre casing flexure 'working' the rubber in the tread and sidewalls. Ambient and track temp only contribute to the temp and pressure rise.

When I said "ambient temp" I wasn't being absolutely clear, the ambient air temp doesn't really cause a pressure rise because ambient air temp is the same on track as in the pits, but in the pits the kart is under shade, and on track it may well be in hot sun, so may pick up radiant heat (in addition to conductive heat from the track surface). Only if ambient temp rises during the day (probable) will this cause any pressure increase.

[QUOTE=Merlin086;1467352]
with a fraction of the volume of air that a car tyre has. And the reason for using nitrogen you are relating to expecting better performance,but only in regard to possibly having the incorrect pressure in the first place. [QUOTE]

Volume may affect the pressure rise, but I have my doubts. My understanding is that for a given temperature rise volume X of gas will incease pressure by Ypsi, regardless of the value of X.

My kart tyre pressures were usually pretty close to spot on, at least for my set up. The karts using nitrogen were also well set up by people who knew what they were doing, their pressures would have been pretty right too. One advantage possible with nitrogen is that you can start the race with a little more psi, which tends to bring the tyre 'on' just a little sooner.

[QUOTE=Merlin086;1467352]
I was a sceptic like you, but the more knowledge I gained, the more I found that I have the ability to make my own judgement.
IMHO it is a economical investment, and a very small price to pay for the possible benefits.[QUOTE]

Please, make your own judgements. I'm not saying it's a bad thing to do, it won't hurt at all and may have a slight benefit, just IMO not a benefit likely to be great enough to be noticable with a road car. If you want to spend the money then fine, but it won't improve fuel consumption to any degree whatsoever, and may or may not contribute slightly to improved tyre wear (depending on the base inflation).

You haven't refuted my comments on water getting into the tyre by the use of water based mounting lubes. If this occurs (and I've yet to see a tyre retailer not use a water based lube), then any potential gain you may get from the nitrogen is moot, it will be utterly negated by the moisture introduced by the lube (which will dwarf the quantity of moisture you'll get from compressed air, i.e. any potential advantageous affect of the dry nitrogen will be all but totally overwhelmed).

[aaronng]

Im getting that rechargeable 18v handheld air compressor from aldis today for $39.95. Never have to line up at caltex again.

Good luck. I find the 12v cigarette socket one very slow especially when trying to reach the last few psi on the way to 36.

[JohnL]

Well i'm telling you for a fact that i get 1-2psi loss over a 2-3 mth.period. (i've been using Nitrogen for approx.8 years)With just air in my tyres i used to lose more than 1-2 psi over the same period.I run 40psi all round.

I don't dispute this possibility, Nitrogen is a physically large atom (as atoms go!), and passes less easily through the matrix of rubber molecules than do some (all?) of the other gasses making up air, possibly slowing slow deflation through the tyre wall over an extended period.



If you have a leak of course it doesn't matter what gas/gasses are in the tyre:rolleyes:

I said; "Not checking the pressures for any extended period is asking for trouble". I said this because you said (about using nitrogen); "don't have to check pressure for 2-3 months". If you lose negligible pressure over your 2-3 month period then you're lucky, but if you get a slow leak then you could be in trouble, nitrogen doesn't come into it.

[JohnL]

Good luck. I find the 12v cigarette socket one very slow especially when trying to reach the last few psi on the way to 36.

I had one of those. It died attempting 45psi (poor thing, would have been a PB for it!).

[one4spl]

All those low voltage things are shite.

You can get a decent compressor from bunnings, supercheap, etc for $100ish.

I recently saw an orange upright one at bunnings for $100ish that a guy that came to repair our pool used for diving... on the basis that if he used it for a couple of hours each day and it still worked it must be fairly reliable.

I guess that the lack of significant tank would limit its burst capabilities though for doing stuff like blowing and powering high speed tools, though.

[one4spl]

There are no free rides in fuel economy as in life. There is no magic bullet.

Maintain your car (and its tyres), drive gently, or even better don’t drive it as much in the first place.

Anything dramatic you may do to improve its economy will either make it less safe or cost a fortune, negating the whole point.

Buy a smaller car (or bike?) if you are having trouble paying for your big cars appetite, or buy a hybrid if you have money but want to save the planet.

HTH, Luke

[aaronng]

All those low voltage things are shite.

You can get a decent compressor from bunnings, supercheap, etc for $100ish.

I recently saw an orange upright one at bunnings for $100ish that a guy that came to repair our pool used for diving... on the basis that if he used it for a couple of hours each day and it still worked it must be fairly reliable.

I guess that the lack of significant tank would limit its burst capabilities though for doing stuff like blowing and powering high speed tools, though.

With compressors, you should use them regularly. If you leave them in storage for a few months, you'll find that you'll get leaks and eventually the seals in it will fail.

[aaronng]

There are no free rides in fuel economy as in life. There is no magic bullet.

Maintain your car (and its tyres), drive gently, or even better don’t drive it as much in the first place.

Anything dramatic you may do to improve its economy will either make it less safe or cost a fortune, negating the whole point.

Buy a smaller car (or bike?) if you are having trouble paying for your big cars appetite, or buy a hybrid if you have money but want to save the planet.

HTH, Luke
True, but the Euro is still pretty good for what it is (2.4L). I just did Melb to Sydney for both the Euro (manual) and a 2002 1.8L Astra (auto). Fuel consumption on the freeway and in the city were the same! Mind you, the rpm on the freeway was very similar with both cars. The Euro was at about 2600-2700rpm while the Astra was at 2700-2800rpm.

[JohnL]

True, but the Euro is still pretty good for what it is (2.4L). I just did Melb to Sydney for both the Euro (manual) and a 2002 1.8L Astra (auto). Fuel consumption on the freeway and in the city were the same! Mind you, the rpm on the freeway was very similar with both cars. The Euro was at about 2600-2700rpm while the Astra was at 2700-2800rpm.

Is the Astra the hatchback variant? If so then my guess is that at least a part of the reason for the similar economy between the Astra and the Euro in highway driving is aerodynamic(?). Hatchbacks have inherantly poor aerodynamics because the rear of the body ends too abruptly (like the rear end of a brick!), and you get a lot of turbulent airflow behind the car. This means that there is a large low pressure zone behind the car (or at least larger and / or lower than with a better body shape), making it harder to 'push' the car through the relatively higher high pressure zone in front of the car.

On the other hand, Honda sedans tend to have fairly slippery shapes and thus a smaller and / or less low low pressure zone behind the car (a lower coefficient of drag), partly due to the more gradual tapering off of the rearward part of the body. This makes ot easier to 'push' it through the frontal high pressure zone, even if this may be no higher than on other cars.

We have two cars, one a CB7 Accord (2.2L manual), the other a late model Mazda 323 hatchback (1.8L auto, with lock up converter). Both are driven regularly on dirt roads and the more turbulent flow behind the Mazda can be inferred from the heavy build up of dust that very quickly adheres to the rear window and panelwork.

The Honda however remains much cleaner for a lot longer, and with most of the dust building up just on the rear of the boot lid (just the near vertical part), and on the rear bumper. The Accord can go as low as 6.3L per 100km on the open road, which is very good for a fairly heavy mid size car with a 2.2L engine. I haven't actually checked the Mazda's econmy, but I'd be surprised if it were much better (or no better) despite being lighter with a smaller and later modern engine.

[aaronng]

Is the Astra the hatchback variant? If so then my guess is that at least a part of the reason for the similar economy between the Astra and the Euro in highway driving is aerodynamic(?).
No, the Astra is the sedan version. While the very low drag coefficient of the Euro will surely help at freeway speeds, it still doesn't explain the consumption in city driving (max 60km/h if not under heavy traffic jams). Would having a manual gearbox offset the smaller capacity and lighter weight of the Astra? I reckon the k24a3 engine has some pretty efficient tuning for part throttle low to mid RPM.

[JohnL]

Agreed, aerodynamics is a non issue around town, but you said this was on trips from Sydney to Melbourne? Not a hatchback either, oh well there goes another perfectly good theory! Well not completely, shorter bodied cars also tend to be less aerodynamic than longer bodied cars (all else being equal). Even being a sedan I'd imagine the Astra likely to still be aerodynamically less efficient (drag), but the Euro would have a larger frontal area offsetting it's superior shape to some degree, it would depend on just how 'draggy' the shorter Astra body was.

As you suggest, a lot of it may just be that the Euro has a more sophisticated / better sorted engine package than the Astra (i.e. engine design / build, EFI / ignition mapping etc). It may also be that there were other smaller contributing factors, tyre pressures, poorer maintenance etc.

The greater weight of the Euro (or any heavier car) is far less contributory to poor economy on the open road, once all that inertial mass is up to speed it doesn't have much affect on economy unless the terrian is quite hilly or twisty (slow down, speed up, slow down...). Around town you pay and pay for it at the bowser, weight always costs in city traffic so it's surprising the Astra isn't further ahead on this front in town, perhaps the torque converter is to blame (not locking up enough?). Might be that the Astra is more underpowered than the Euro, so gets thrashed harder to keep up?

The slush box will have some affect (worse consumption), more so in town than on the hwy. This is assuming the tranny has a lock up converter, which I expect it would, they pretty much all do these days. In town the converter will spend more time 'un-locked' and thus more time converting wanted engine power into unwanted heat (the torque converter may well multiply torque to the wheels, but it loses power i.e. actual energy). On the hwy the converter would spend a lot more time locked and acting as a solid connection between tranny and engine, losing no energy at this point, rather than being a fluid connection wasting power.

[JohnL]

Try reading this..
http://ezinearticles.com/?Selling-Nitrogen-In-Tires---Is-It-All-A-Lot-Of-Hot-Air?&id=38142

I read the article in your link, thanks for providing it.
I’ve quoted some of it below (with some of the more irrelevant statements deleted by me), along with my comments in bold. James Burchill (the author) wrote:

Remove The Oxygen And Stop The Rot
To stop this decomposition you simply need to remove the oxygen from the ‘air’. (Incidentally, removing oxygen also means that you remove water because water is two parts Hydrogen gas, and one part Oxygen gas.)

Oxygen in the tyres is not ‘nice’, but it’s not a big deal. Whatever you do, you can’t stop oxygen attacking the outer surface of the tyre, which is where it “rots” that part of the rubber that actually creates grip (tends to harden it somewhat over time).

Oxygen inside the tyre does relatively little harm, and by the time it does any appreciable damage (if it does any appreciable damage) then the rubber on the outside will be much worse because of oxygen attack as well as the degrading affects of sunlight. Note that old tyres tend typically to start cracking from the outside, not the inside.

Removing oxygen from the air will remove oxygen gas, oxygen atoms bound up in water is a different beast and a separate issue to gaseous oxygen.

Removing Oxygen from products is not new, we do it all the time with our food and drink. In fact, if we did not remove the oxygen our food would not likely last long enough to make it into the hands of the consumers – or it would taste stale and unappealing.

Sure, oxygen is an oxidising agent, but food is not tyres. An utterly irrelevant analogy!

Here are a few other benefits of using Nitrogen in tires:
[1] Nitrogen is denser than Oxygen: This means the larger molecules escape less easily from tires resulting in a more gradual loss of pressure over time. According to the Michelin Tire Manual, a tire that is inflated with Nitrogen loses its pressure 3 times slower than if it were inflated with air.

In principle I agree. Not sure about the “3 times” figure, seems hard to reconcile this with nitrogen being 78&#37; of the air content. It might be correct (hmmm) but even if so you lose air very slowly from a sound tyre inflated with air (I had a kart tyre originally inflated to 20psi, after a few years sitting in the back of the garage it still had about 10psi in it), so if you check the pressure regularly then it’s no big deal (and you should check regularly in case you develop a slow leak, it’s far from uncommon).

Even assuming this to be absolutely correct, this is potentially dangerous info if it leads you into not regularly / frequently checking tyre pressure (or leads someone into recommending that you don’t), don’t let this lull you into a false sense of security!

[2] Nitrogen is moisture free:

Misleading. Nitrogen is not moisture free because of any innate property, it’s only moisture free if it contains no moisture (to state the obvious). It’s dryness from the cylinder can be compromised by water based mounting lubes and from any water pre-existing in the tyre, defeating the real purpose of using it.

Pure Nitrogen inflated tires experience less steel belt and rubber degradation. Nitrogen use also reduces valve and wheel corrosion.

Not completely untrue, but… The steel belts are not likely to be in contact with the internal water unless the tyre case is damaged. The rubber is more or less immune to water. In 30 years of driving the last time I had a corroded valve was, um, let me think…never! (not to say this is impossible). I’ve had steel wheels with areas of paint missing where it was exposed to internal air for years, only light surface rust (scrubbed most of it off with scotch-brite).

[3] Nitrogen provides longer tire life: Nitrogen inflated tire run cooler and require less maintenance according to the Goodyear application bulletin.

Apart from the dubious advice about less maintenance (might well lose less psi over time with N, but still needs to be checked just as often as with air), this is either incorrect or so dependant on other un-stated variables as to be effectively untrue. I don’t know who within Goodyear writes the ‘application bulletin’, but I bet it’s not a senior tyre engineer, or, someone might be being quoted out of context (?).

All dry gasses expand with heat at the same rate, so with X temp rise the pressure rise will be the same regardless of the gas. Gas (whatever it is) picks up heat from the tyre tread and sidewalls, and continues to pick up heat until it reaches the same temp as the tyre itself. All else being equal (track temp, grip / friction level, degree of tyre deformation), the tyre itself will pick up heat as a function of pressure (as this will affect tyre deformation and possibly contact patch size etc), it won’t ‘see’ any difference in the chemical composition of that pressure.

Nitrogen won’t ultimately pick up less heat because it’s chemically different, but theoretically is likely to conduct heat at a differing rate than other gasses. I don’t know if nitrogen is more or less conductive than air, but since air is 78% nitrogen it’s not likely to be greatly different either way (the difference will most likely be a lot less than the 22% remainder because these gasses still also conduct heat even if to differing degrees than N).

In any case, thermal conductivity of all gasses is poor (your thermos would work acceptably no matter what gas it contained), and would be more of an issue in ‘still’ gas, but the gas inside the tyre will be quite agitated which will dramatically speed up the rate at which it picks up heat from the tyre. In either case (nitrogen or air) the highly agitated gas will pick up heat very quickly because the agitation causes more of it to come into close contact with the tyre wall (gas temp then lagging only slightly behind the temp rise of the tyre itself) and any difference in heat pick up between the gasses is likely to be so small as to be academic.

All gasses are the same as far as pressure, temperature and volume are concerned. I.e. all gasses will have the same pressure if the temperature and the volume are the same, or will have the same temperature if the pressure and volume are the same, or will have the same volume if the pressure and the temperature are the same. If any one of these three parameters change then at least one other and maybe both others will change, and the affect will be identical in any gas. This is so much so that if we had two absolutely identical tanks filled with any two different gasses and both these tanks were at absolutely identical pressure and absolutely identical temperature there would be an identical number of gas molecules in both tanks, despite the gasses being different.

There is nothing magic about nitrogen in this respect, it obeys the ‘universal gas law’ (more or less roughly described in previous paragraph), which is fundamental to all of this stuff about nitrogen vs air used in tyres. The identity of the gas in the tyre is really a non issue, the only real issue here is whether water is or is not present in the tyre, and the affect this may have on pressure rise with tyre temp.

It’s an issue because within the range of temperatures found inside a tyre water can be either a liquid or a gas, and physically behaves very differently in these two completely different states. Gasses on the other hand all physically behave very similarly, if the water in the tyre never condensed into a liquid then it wouldn’t be an issue, but it does.

[4] Nitrogen is non-flammable: Nitrogen technology has been used in aircraft, military and race car technology for over thirty years.

The non contribution of nitrogen to the burning of other materials is a complete non issue for tyres used on a road car. Tyres on fire? Probably the least of your troubles I’d think!

And, oxygen isn’t flammable like say hydrogen, it doesn’t burn per se, you can’t set fire to it, but I’m splitting hairs! Any oxygen in the tyre that could conceivably contribute to the burning of any part of the car will be absolutely insignificant compared with atmospheric oxygen, which is freely available to the fire and in effectively endless supply.

Nitrogen is used in top end racing, but is overkill for a road car. Why would aircraft use nitrogen? Might not want water freezing solid inside the tyre…(?). Different application to cars, not relevant.

But can we expect ‘Joe Consumer’ to start paying for this new ‘air’ anytime soon? As always, the answer is “it depends.” If enough businesses and corporations get behind the idea and promote it steadily, uniformly and explain the numerous safety and cost savings, then eventually the message should make it through.

Doubt it very much, the “message” isn’t exactly bogus but it just isn’t quite as ‘advertised’ here, and even if it were I can’t see much money to be made considering ‘promotional’ costs. If the major car companies saw any real benefit to themselves and their customers then they would probably at least recommend or suggest the use of nitrogen, but they don’t and they won’t.

It’s Still Weird Science

It’s not weird, it’s perfectly ‘ordinary’ science, but it seems to be somewhat misunderstood and misapplied for road car tyres!

Regular air is approximately 80% nitrogen anyway, are we to believe that an extra 20% makes all the difference… Ironically we now know that the answer is yes.

It just doesn’t, not for a road car, unless we define “all the difference” as a very very slight difference! High end race cars are a different story, every little bit helps in competition. Here’s a question; what manufacturers of very high performance road cars specify the use of nitrogen in the tyres? Are there any? There might be but it would be news to me.

You and I both know that if using Nitrogen means your client’s tires last longer they will save money by not having to purchase as many tires.

The “client’s” will save next to or actually nothing on tyres whether or not they use nitrogen or ordinary air.

JAMES BURCHILL is an experienced Internet Marketing & Business Development specialist providing strategic and tactical solutions to select clients seeking to architect their on and off line marketing success. James was the architect behind one of the CAA's most successful ad campaigns in their 100 year history, and for pioneering Goodyear's Internet marketing strategy. He's also is a published author, a passionate advocate of technology and the Internet, as well as an avid study of classical advertising and marketing strategies. Prior to establishing his own unique consulting practice, he served as VP of Professional Services and VP of IT & Consulting and implemented multi-million dollar solutions for Oracle, the British and US Governments, Rolls Royce UK and many others. James taught Computer Science at one of Toronto's leading colleges and continues to coach private clients on a select basis.

In what way does this CV qualify the author of this article as a tyre expert? His stated background lends him no credibility in this, the guy is not an engineer of any description, he is a marketing man (what is he selling and who is he selling it for?).

Check out that marketing speak, e.g. “tactical solutions to select clients seeking to architect their on and off line marketing success”. What a wank, give me a break!

[akina]

... totally lost interest in this thread, WAY too much to read... i cbf.

[Pumped]

LOL,
400 line posts ftl

[aaronng]

Agreed, aerodynamics is a non issue around town, but you said this was on trips from Sydney to Melbourne? Not a hatchback either, oh well there goes another perfectly good theory! Well not completely, shorter bodied cars also tend to be less aerodynamic than longer bodied cars (all else being equal). Even being a sedan I'd imagine the Astra likely to still be aerodynamically less efficient (drag), but the Euro would have a larger frontal area offsetting it's superior shape to some degree, it would depend on just how 'draggy' the shorter Astra body was.
I drive both cars regularly. Full city driving in Melbourne for the past 9 months and then recently (last 2 weeks), I drove both cars (one at a time) from Melb to Sydney. I was surprised that the Astra didn't get better fuel economy under both city and highway conditions.



The greater weight of the Euro (or any heavier car) is far less contributory to poor economy on the open road, once all that inertial mass is up to speed it doesn't have much affect on economy unless the terrian is quite hilly or twisty (slow down, speed up, slow down...). Around town you pay and pay for it at the bowser, weight always costs in city traffic so it's surprising the Astra isn't further ahead on this front in town, perhaps the torque converter is to blame (not locking up enough?). Might be that the Astra is more underpowered than the Euro, so gets thrashed harder to keep up?
That's the part that surprised me. The Astra wasn't trashed (driven below 3000rpm and part throttle) and it's even driven around with an empty boot. The Euro's boot is always half-full with tools and detailing equipment. Tyre pressures are checked monthly by me and set to the right psi (34psi for city, 36psi for highway) and servicing is done by the dealer at the scheduled intervals.



The slush box will have some affect (worse consumption), more so in town than on the hwy. This is assuming the tranny has a lock up converter, which I expect it would, they pretty much all do these days. In town the converter will spend more time 'un-locked' and thus more time converting wanted engine power into unwanted heat (the torque converter may well multiply torque to the wheels, but it loses power i.e. actual energy). On the hwy the converter would spend a lot more time locked and acting as a solid connection between tranny and engine, losing no energy at this point, rather than being a fluid connection wasting power.
Yup, I was really expecting to get 6L/100km from the Astra but it was still the same 7L/100km like the Euro. :(

[aaronng]

I'd like to add, nitrogen is not more dense than oxygen. Nitrogen has a density of 1.251 g/L, while oxygen has a density of 1.429 g/L. Oxygen is MORE dense than nitrogen. Hence that article loses credibility.

[JohnL]

I'd like to add, nitrogen is not more dense than oxygen. Nitrogen has a density of 1.251 g/L, while oxygen has a density of 1.429 g/L. Oxygen is MORE dense than nitrogen. Hence that article loses credibility.

Aaron, I'm happy to accept your numbers, I don't know offhand the densities of these gasses (pretending that I might happen to know the densities of quite a few others...!). My understanding (which may or may not be correct) is that N is a physically large (largest?) gas molecule, this being the reason why pressure loss over extended periods is somewhat less with N than air.

The article leaks it's credibility with every sentence like a slashed tyre losing nitrogen!

[power_of_dreams]

JohnL and aaronng know their shit.

[JohnL]

... totally lost interest in this thread, WAY too much to read... i cbf.

The tough keep going, the weak fall by the wayside!!

[JohnL]

Yup, I was really expecting to get 6L/100km from the Astra but it was still the same 7L/100km like the Euro. :(

That's Honda for you, that's Holden for you!

[JohnL]

JohnL and aaronng know their shit.

I will soon, Doc gave me a bowel testing kit yesterday!

Don't take all I say as gospel. I don't lie but really it's just IMO and I do make errors (sometimes!). I know a reasonable amount about a lot of different things, but am an expert on very few!

[aaronng]

Aaron, I'm happy to accept your numbers, I don't know offhand the densities of these gasses (pretending that I might happen to know the densities of quite a few others...!). My understanding (which may or may not be correct) is that N is a physically large (largest?) gas molecule, this being the reason why pressure loss over extended periods is somewhat less with N than air.

The article leaks it's credibility with every sentence like a slashed tyre losing nitrogen!

Yes, the nitrogen molecule is the largest gas molecule.

To me, air consists of 78% nitrogen, and using nitrogen only slows down the pressure loss of the remaining 21% oxygen and 1% other gases. To me, that is not really a tangible benefit of using nitrogen. Instead of nitrogen, I'd use dry air instead.

[aaronng]

I'm still learning too. I got schooled by JohnL in the spring compressor thread. :)

[JohnL]

Yes, the nitrogen molecule is the largest gas molecule.

To me, air consists of 78% nitrogen, and using nitrogen only slows down the pressure loss of the remaining 21% oxygen and 1% other gases. To me, that is not really a tangible benefit of using nitrogen. Instead of nitrogen, I'd use dry air instead.

Agreed, but I still wouldn't bother unless it was for my fantasy racer. Nitrogen tends to be used more or less by default because it's the most commonly available bottled gas at a reasonable price. Dry air in tanks might well be available, I don't know how easily, most people wanting compressed air will get it from a compressor, and most of those don't care too much about a bit of moisture (spray painters don't like it though!). No reason others couldn't be used, argon might be good, very inert I understand?

[aaronng]

Yup, Argon will work and it's reasonably priced too.

Then again, even air is sufficiently inert for tyre inflation as long as it doesn't contain too much moisture. My opinion is that using an inert gas might protect the insides of the tyre, but the outside, the important tread material will still suffer the brunt of pollution, UV and dog pee. The difference in tyre life span between using air and nitrogen/argon should be negligible since the outer tyre surface gets hardened at a much quicker rate than the inside surface.

[JohnL]

I wasn't really suggesting argon in particular as an alternative to either nitrogen or air, just meaning that a number of gasses other than nitrogen could be used just as effectively for the same reason nitrogen is used, which is legitimate in the right context and harmless outside that context. Some gasses would be ill advised, e.g. pure oxygen, or hydrogen, or helium, or...

Air is indeed inert enough for the purpose of tyre inflation, though my preference would be that the compressor was at least fitted with a dehumidifier if possible. The biggest issue would be the wet tyre lube, i.e. stopping the tyre joint from using it (probably need to take our own tube of 'rubber grease', and put up with the muttering and bad vibes!).

[power_of_dreams]

Went to 3 servos last night to change my tyre pressure. First one had a hole in the piping and was taking years, so I went down the road. This one kept repeatedly giving me error message "err2". Went to a third servo, and encountered some problems.

When changing tyre pressure will it release some air first (regardless of current pressure) and then pump it back up to desired pressure? Because I plugged it in, the screen read 29 then pumped all the way up to 35 (what I want). Then I double checked, put it back in and it read 29 or so again before pumping up to 35. Somtimes it went the other way and did 39 down to 35. Got a couple of error messages inbetween as well. I was there for ageeeeees trying to figure it all out.

[one4spl]

Some of those servo electronic tyre setups are really good, and as you've seen, some suck balls.

I have my own gauge that I double check with.

I just found this in The Googlez-

http://racq.com.au/images/documents/Tyre_pressure_gauge_survey.pdf

An interesting read, and agrees with my personal experience.

I'd buy a decent brand-name dial gauge of your own to double check the servo's system.

[aaronng]

When changing tyre pressure will it release some air first (regardless of current pressure) and then pump it back up to desired pressure? Because I plugged it in, the screen read 29 then pumped all the way up to 35 (what I want). Then I double checked, put it back in and it read 29 or so again before pumping up to 35. Somtimes it went the other way and did 39 down to 35. Got a couple of error messages inbetween as well. I was there for ageeeeees trying to figure it all out.
That gauge was probably broken. I bring my own gauge and use their pump to fill my tyre.

[tony1234]

That gauge was probably broken. I bring my own gauge and use their pump to fill my tyre.
NEVER rely on the servos gauge,bring your own.

[power_of_dreams]

Found one of these in my garage!

http://www.gear4bikes.com/images/workshop/tools/H500005.jpg

Luckily too, my passenger side tyres were both ~38. My drivers side was ~36

[SPQR]

Most things in the driving environment cannot be controlled. For example, the car's computer has a map that determines the amount of fuel injected based on inputs of air temperature, engine temperature, throttle position, load, air density etc.

It seems to me that the only things within the control of the driver are maintenance (correct tyre pressure, servicing, cleaning the dust off for less drag (only joking), weight, and driving style. Master these and you'll use less petrol.

The owners manual has some information on reducing fuel consumption.

Otherwise, my wife had a Jazz. Compared to my Euro, It cost less. It was smaller (on the outside only; much bigger inside). It wasn't as fast. It used a lot less petrol.

[power_of_dreams]

Jazz was bigger inside?

[johnprocter]

wtf i find that hard to believe that a jazz is bigger inside compared to a euro :S

[IVTECS4]

Currently at the moment, my Euro has been getting near consistent fuel consumption- due to the tires (205s) putting in 36psi and front and back,

The car can between 550-600+(though the highest I got was 620, close to the quoted 10 litre for the auto listed in the manual), as I drive to the city everyday and plenty of freeway driving( I do a Degree course in a private institution in the city). I find that everyday I drive to work in suburbia , it is harder on the fuel - maybe due to changing conditions(?!!) , but still by the time the yellow light turns on the trip computer is displaying 510.

I could never the figures listed above when I used to set the tires to the recommend psi ( 32 front and 30 back) and used to get 440 and the yellow light was on.

[SPQR]

Jazz was bigger inside?

The Jazz has more usable interior space; although not as comfortable as the Euro which cocoons you in nice place.

When my wife and I moved to a house, I could only fit one 90 litre (70cm x 48cm x 40cm) plastic storage box in my Euro; not inside but in the boot. I could not get any inside because the front area is not designed to carry things that big and the back doors do not have a sufficiently large opening to get that size box inside.

With the all the seats down except for the driver's seat, we could get eight (yes I said 8) 90 litre storage boxes into the Jazz at one time with space for odd size things left over. The Jazz is an impressive "load-swallower".

[BiLL|z0r]

I find the interior space of the Euro is terrible too. My work collegue gets heaps more in his Excel then I can in my Euro.

[one4spl]

kilometers per tank is a fairly useless way to measure economy.

You need to measure the fuel going scientifically, as stated before you need to fill the car till the pump clicks, drive it, and then do the same, taking note of the kilometers traveled and the litres needed to re-fill.

then get the litres and divide it by 100's of kilometers-

So a 624km trip, that took 54l to refill after would work out like this-

54l / 6.24 = 8.65 l/100km

!!

[tron07]

The Jazz has more usable interior space; although not as comfortable as the Euro which cocoons you in nice place.

When my wife and I moved to a house, I could only fit one 90 litre (70cm x 48cm x 40cm) plastic storage box in my Euro; not inside but in the boot. I could not get any inside because the front area is not designed to carry things that big and the back doors do not have a sufficiently large opening to get that size box inside.

With the all the seats down except for the driver's seat, we could get eight (yes I said 8) 90 litre storage boxes into the Jazz at one time with space for odd size things left over. The Jazz is an impressive "load-swallower".

When I move, just 1 room of stuffs... I have to make 6 trips with my Euro :p

[tony1234]

When I move, just 1 room of stuffs... I have to make 6 trips with my Euro :p
Buy a Jazz tron07.:D

[power_of_dreams]

The Jazz has more usable interior space; although not as comfortable as the Euro which cocoons you in nice place.

When my wife and I moved to a house, I could only fit one 90 litre (70cm x 48cm x 40cm) plastic storage box in my Euro; not inside but in the boot. I could not get any inside because the front area is not designed to carry things that big and the back doors do not have a sufficiently large opening to get that size box inside.

With the all the seats down except for the driver's seat, we could get eight (yes I said 8) 90 litre storage boxes into the Jazz at one time with space for odd size things left over. The Jazz is an impressive "load-swallower".

What about Euro with seats down?

[SPQR]

What about Euro with seats down?

No. The hatch in the back seat-rest has a pathetically small opening.

Anyway, remember that this thread is about reducing Euro fuel consumption. To me that still means:

1. Proper maintenance without spending more than you'll get back in improved fuel consumption. This for me rules out 98 R.O.N. petrol because in Darwin it's about 15 cents per litre dearer than 95 R.O.N. (the grade recommended by Honda anyway). Oils no more fancy than required by Honda. And free air.

2. Reducing unnecessary weight (I'm on a diet).

3. Driving smoothly. No sudden starts when you're just commuting. No point winning the traffic light grand prix.

I have kept every petrol receipt since new and I record the distance travelled between each re-fill: A full tank each time is the only way to calculate the rate of fuel use. This feed-back is important if you wish to adjust your driving style to use less petrol.

[btchia]

kilometers per tank is a fairly useless way to measure economy.

You need to measure the fuel going scientifically, as stated before you need to fill the car till the pump clicks, drive it, and then do the same, taking note of the kilometers traveled and the litres needed to re-fill.

then get the litres and divide it by 100's of kilometers-

So a 624km trip, that took 54l to refill after would work out like this-

54l / 6.24 = 8.65 l/100km

!!

I agree with you, i remembered one trip i have travelled 720km, fuel light still haven't switch on yet, but indicator not point to E yet. i thought is something wrong with it. After i reach a petrol station, the light just on.... i pumped 55L petrol, that's the longest distance i travelled on my Euro...

Only 7.6L/100km :thumbsup:

[ROBERT]

As 'one4spl' stated the only true way to work out the consumption is fill to fill. I also take note of the price and add that to my spread sheet to determin cost per kilometer.
My average consumption from the car being new (an auto by the way) and over 28,000 km is 7.43 l/100km, my best tank full is 6.5l/100km (Queensland to NSW), so far I have spent $2,650 on fuel and my average cost works out at $0.98 per 10km, or aprox 10 cents per km. I drive on the speed limits but avoid hard acceleration. I do ocasionally rev hard to bring in the VTEC (once every month or so). I also make sure I don't carry around and unecessary weight.

[JohnL]

As 'one4spl' stated the only true way to work out the consumption is fill to fill. I also take note of the price and add that to my spread sheet to determin cost per kilometer.
My average consumption from the car being new (an auto by the way) and over 28,000 km is 7.43 l/100km, my best tank full is 6.5l/100km (Queensland to NSW), so far I have spent $2,650 on fuel and my average cost works out at $0.98 per 10km, or aprox 10 cents per km. I drive on the speed limits but avoid hard acceleration. I do ocasionally rev hard to bring in the VTEC (once every month or so). I also make sure I don't carry around and unecessary weight.

Robert,
I agree, fill to fill and careful records is the only way to know, "I get X per tank" is an utterly useless measure.

By the way, is that your Cobra replica in your avatar? Nice toy. I'm quite near you, just the other side of Taree, but you probably wouldn't want to get together because I'm likely to put the hard word on you, for a drive of the Cobra that is!

[ROBERT]

JohnL I have sent you a personal message and yes that is a replica Cobra so I use that to get my speed/hard acceleration needs out of my system instead of using the Honda. My fuel consumption for the Cobra is aprox 18l to 20l/100km, I don't keep acurate figures for it as I don't really want to know, and it's not about saving fuel, it's about having a good time.

[tron07]

What about Euro with seats down?

Even with the seats down, the opening of the boot is not huge to fit in big boxes... compare to jazz, which is a hatch, and the lid open upwards, you can fit big boxes thru the back. But with Euro, big box cant go in, but long boxes can go in with the seat folded down.

[power_of_dreams]

Even with the seats down, the opening of the boot is not huge to fit in big boxes... compare to jazz, which is a hatch, and the lid open upwards, you can fit big boxes thru the back. But with Euro, big box cant go in, but long boxes can go in with the seat folded down.

spose so..

[johnprocter]

i just checked my tyre pressure (i have the stock 16" wheels and some normal tyres nothing fancy) and they were all on 40psi i put them down to 34psi, whats the downfall of having a high psi like 40? would that increase fuel consumption or ?

[Merlin086]

i just checked my tyre pressure (i have the stock 16" wheels and some normal tyres nothing fancy) and they were all on 40psi i put them down to 34psi, whats the downfall of having a high psi like 40? would that increase fuel consumption or ?

Will improve fuel consumption.........:thumbsup:

But then you will wear your tyres in the middle and handling will be..:thumbdwn:

......no flex.....:(

[JohnL]

Will improve fuel consumption.........:thumbsup:

But then you will wear your tyres in the middle and handling will be..:thumbdwn:

......no flex.....:(

Be careful of blanket statements. With higher psi, whether the tyres will wear in the middle or not, and whether the handling will be worse or better, will depend on the tyre, the psi and the load carried on the tyres. Many tyres will handle better at higher psi, others less so.

Right now I have 38psi in my front tyres and 45psi in the rears (stock size 195/60/15). Neither front nor rear are wearing abnormally, and grip / handle better at these pressures than when pressure is reduced (I've experimented with this quite a lot). Note that these pressures work with the particular tyres fitted to my car, and the tyres are a different brand front and back (reflected in the different psi I have in the front vs rear).

Not all tyres will like 45 psi, my front tyres behave strangely at 45psi, but quite OK at 38 (and less well below this). My rear tyres are good at 45psi, but feel and act as if underinflated at 38psi...

[tron07]

Emmm... we are talking about Euros... and they dont come with 15"

[JohnL]

Emmm... we are talking about Euros... and they dont come with 15"

All my statements above apply in general to all tyres, the principles are identical regardless of tyre size or car etc. Where I mentioned specific pressures I made it clear that these pertained to the particular tyres I have fitted on my car. Please read my post more carefully.