What tyre pressure?

[spetz]

What tyre pressure should I have?

The tyres are 205/45/16 Bridgestone S-02 Potenza
Front weight is 740kg, rear 380kg

At the moment I am running 39psi front, 37psi rear but thinking of lowering each side by 1-2psi

[iceman91]

thats a wee bit too much... i would be looking at the 28-32 psi...

[spoondc2]

What car is it?
just try F32psi R30psi

[spetz]

That sounds too little?

I thought lower profile tyres needed higher psi?

I thought, 34psi is about as low as I could/should go??

[spoondc2]

That sounds too little?

I thought lower profile tyres needed higher psi?

I thought, 34psi is about as low as I could/should go??

not really....
it's not really about the tyres, it's about how heavy your car is

[saleeb]

depends how long u want ur tires to last, too low and u get wear on the outsides of the tires, too little and u get less grip, they should have a max amount on them then u can go a little lower than that, unless ur going to the track then go a lot lower.

[iceman91]

ideal pressure varies between 28-32 psi, i have maintained 29 psi in all four for most of my cars and never had a problem with them. low profile tires too...

[DomenEK]

It all depends on the car and the tyres.

I have 205/40/17s on my EK1 sedan, and ran 34 all round for a while, but found it wasn't ideal. After playing around with the pressures, I found that 39-40f and 37-38r works best for my car and tyres.

Muck around with the pressures, but you may find that they need to be about 36/37 front and 34/35 rear.

[aaronng]

I have 205/55 R16, car weighs 1400kg. I use 36psi. I wonder if there is a correlation between weight, profile and psi?

[socheerio]

spetz has a lancer coupe with a V6 conversion. Sounds to me that, with 45 series tyres, you should be looking at 38-ish front, 34 rear and experiment 2 psi either side of that.

[n/a]

you guys are crazy.. i never go above 34.. 32 is what i normally have.

[iceman91]

look at the standard pressure rating..i dont see anything above 32psi...39-40 is too high..

[Slow96GSR]

Look at the tag on you door or hood and see what Honda says or better yet look at the side wall of the tire.

[hotboxcivic]

Look at the tag on you door or hood and see what Honda says or better yet look at the side wall of the tire.

Honda tyre ratings would be for Honda Stock profile and sizes. if you have different sized rims and lower profile the rating would be of no use.

[Slow96GSR]

That's why I said look at the tire's side walls too! Guessing will get you in more trouble then it worth. It is better to just look at the tire then ask someone who assumes it's 29-32psi. Could be more or less. Just to let you know I run 35psi all around but that's me. I've seen some all the way up to 45psi on passenger cars. My semi took 95 psi and the trailer took 100psi! Our trucks take 50psi and my aunts car 30psi. I'll let you pick what you use! LOL!

[mrwillz]

i use 38psi all round

for 205/40 or 45 i fink shud b 36+ psi

[DomenEK]

Guys - it all depends on the weight of the car and the tyre itself!!

n/a and iceman91 - What tyres are you guys running? Sounds to me like stock sized tyres. The stock tyres on mine were 185/60/14s, and the recommended pressures as per the tyre placard were 32 front and 29 rear (from memory).

When I first got my 205/40/17s I was told to run 34 all round, but I found they were wearing on the outer edges, meaning that there was not enough pressure in them. So I experimented and found that not only did running them at a higher pressure solve the wearing issues, the handling was noticeably better, especially in the wet.

As a general rule of thumb, lower profile tyres require higher pressures to perform at optimum level, and to get maximum tread contact with the road (lower profile tyres are usually wider than stock too, so they require more air to allow full tread contact). Therefore for the 45 series tyres you should be looking at 35+, but your best bet is to ask someone in the know at a reputable tyre place.

[TypeLess]

The tyre placard on your car door is recommended for your stock tyre size, not your modified and lower profile tyres. Plus this recommended pressure set by the car manufacturers is the very minimum amount of pressure you should have in your tyre. In most cases that pressure will not provide a good tyre milage.

Not all tyres are build the same so depending on the tyre construction and the max pressure, and all other factors like weight, ambient temperture &..... so it is best to speak to your tyre fitter for the correct pressure.

What i usually do on my 215/40R17s (with max pressure at 50psi), i pump atleast about 6-8 psi above the minimum pressure recommended on your tyre placard. also do this when your tyre is cold.

[socheerio]

Just a reminder, spetz's car is a modified lancer, so the tyre placard is irrelevant, hence his query :confused: :

2001 Lancer coupe
It has a 6A12 MIVEC engine in it, which is a V6 so it is very nose heavy.
It has 740kg over the front wheels, and 380kg over the rear wheels with little petrol, and no spare tyre or subs.
At the moment, suspension is as follows:
Tein SS coilovers
Anti lift/castor kit
Front upper, rear upper & rear lower braces (will put front lower 4 point brace as well)
Springs are 5K front, 4K rear
18mm front swaybar (want to get a bigger one)
18mm rear FTO swaybar (want to get bigger one)

Further, as typeless says, Japanese manufacturer's placard recommendation is generally a little low for even mildly enthusiatic driving. Add 4-6 psi depending on preferences re ride comfort. PSA products are rather more realistic of late, but even there they err on the low side.

[CB7_OWNER]

higher u run, the more economical your car gets cause of less rolling resistance..the lower you go the higher the ride comfort.....

Higher pressure by about 2-4psi at the front compared to the rear, if you want your car to turn in a bit better apparently...(when your pushing it hard )

32psi is standard/recommended from factory,as its the best compromise for comfort/economy..

[rk 86 wa]

215 40 r17 1150 kg car with 36f 34r

[nd55]

39 f, 34 rear EK civic.

Give your tyres a wipe/wash and then use shoe polish/white marker on the sidewall.

Drive like you stole it for a couple of days and check to what height the marker gets rubbed off.


http://ivtec.forumotion.com/tires-wheels-f10/determining-your-proper-tire-pressure-for-handling-t28.htm
http://mgaguru.com/mgtech/tires/sp101.htm
http://forums.s2kca.com/archive/index.php/t-17819.html
http://nellump.net/peri/hypo/genAutoTechs/tirePressure.html

Nick.

PS. I didn't closely review all the links.
PPS. Your alignment needs to be kosher for this to have any relevance.

[EG30]

bit high for street Spetz.

S02 happiest between 30and 35 psi cold inflation pressure from my pass experience with them. Experiement and see what suits you best.

[ae86hachiroku]

Firstly, I have to ask, what are you doing with the car? Track? Street? Drag?