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rob1000
16-10-2009, 12:07 PM
I've been interested in finding out exactly when my vtec-e is kicking in yo. Mainly so on long cruises i can drive as efficiently as possible ie, on 12 valves.

Assuming vtec-e (16valves) engages at ~3000rpm then i can sit on the freeway at ~ 100km/h in 5th gear. If the light comes on... ease off the speed until the light turns off ...

Anyone done this?

I was reading in this thread a guy simply spliced a LED+capacitor into the grn/yellow cable going from the ECU to the solenoid (i assume?). Is this safe? Seems p1ss easy to do if its fine.

http://www.honda-tech.com/showthread.php?t=2303995

On that topic, I saw in my manual that a "ECO" instrument light is an option on a model of EK. Anyone know if this is used for this very reason OR it might be related to the CVT gearbox?

Thanks for any advice

aaronng
16-10-2009, 12:48 PM
Just run the LED or even a tiny 12V low power bulb from the solenoid. Mount it on your dash and you have your vtec light.

rob1000
16-10-2009, 12:49 PM
Just run the LED or even a tiny 12V low power bulb from the solenoid. Mount it on your dash and you have your vtec light.

Cheers might have to do this :)

Edit: Incase anyone's wondering here's a vtec light DIY
http://www.ozhonda.com/forum/showthread.php?t=16083&highlight=vtec+light

EK1.6LCIV
16-10-2009, 01:08 PM
run shift lights (they have shift lights with 3 or more leds in them to show certain points in the rev range), I have mine set to have one come on at 4000, another at 5000 and another at 6000

when two come on vtec in my lil engine kicks in so it's two guides in one for myself personally

rob1000
16-10-2009, 01:10 PM
sounds good but a bit too much for my lowly vtec-e yo ;)

EK1.6LCIV
16-10-2009, 01:12 PM
cheap set up from pivot didnt cost much to rig up, built in dimmer

SHU-ES1
16-10-2009, 03:05 PM
hey mate,

im running one on my vtec e beast and it's good to know when it comes on but tbh, i dont think it makes much diff as vtec e was made for fuel efficiency rather than power output and the effects it has on fuel consumption are minimal. it's still a nifty little light to have. it's only annoying on the freeway when you're doing 100km/hr+ cos it'll most likely stay on for your whole drive. mine engages at 3.2krpm, and disengages at 3krpm.

i have a 3 led globe to the left of my cluster bezel, and grounded it to one of the cluster bolts. i ran the wire from my vtec solenoid. pm if you need help!

rob1000
16-10-2009, 03:22 PM
ahh cool

hmm yeah thats exactly what i want it for though not for performance but efficiency. Do you find it possible to cruise at 100km without vtec-e enabling? If so it will save a fair bit of fuel.

Recently went for a cruise to hunter valley for the weekend, up and back on 3/4 tank then drove around sydney for the remaining 1/4. Ended up getting 570km from 32litres :) I'm pretty confident i can get 650kms if i was highway driving for the full tank (35lts) especially if i could adjust my cruising using a light so that I'm always on 12valves.

Might grab a dull 12v LED light from jaycar

rob1000
16-10-2009, 03:37 PM
whats funny... i just worked out that on my little hunter trip (assuming of course my math isn't rubbish) ... if i did 570km from 32litres petrol thats 41.48MPG. Thats the same a Toyota prius heh. Boggles my mind why people are so amazed with prius' cars.

- a 1997 vti sedan is over 10 years older
- 50% lighter
- x2 horsepower
- fits more, seats, boot space etc
- cost ~ $4500 - 10% the price of a prius.
- dont' have to replace batteries

SHU-ES1
16-10-2009, 06:10 PM
according to your calculations, you're getting 5.61L/100km. that's is awesome! hehehe.. well done! and yes, i can keep it at 100km/hr without the light coming on. it's only when i'm at about 105-108km/hr thats when the light comes on regardless due to my revs being over 3.3krpm.

aaronng
16-10-2009, 08:04 PM
whats funny... i just worked out that on my little hunter trip (assuming of course my math isn't rubbish) ... if i did 570km from 32litres petrol thats 41.48MPG. Thats the same a Toyota prius heh. Boggles my mind why people are so amazed with prius' cars.

- a 1997 vti sedan is over 10 years older
- 50% lighter
- x2 horsepower
- fits more, seats, boot space etc
- cost ~ $4500 - 10% the price of a prius.
- dont' have to replace batteries

Prius' advantage is in city driving. It is not spectacular on the freeway. If your vti went against the prius in pure city or suburb driving, the prius would win.

rob1000
17-10-2009, 01:38 AM
Prius' advantage is in city driving. It is not spectacular on the freeway. If your vti went against the prius in pure city or suburb driving, the prius would win.

mmm yeah good point also i didn't mention the prius plugin hybrid conversions so you can potentially use no fuel at all upto a certain amount of kms before switching to petrol.

Anyway, I'm now keeping track of how many k's i get in city driving for the current tank but i bet its nowhere near 550-650kms :o

Spoon SiRG
20-10-2009, 10:43 PM
Full tank capacity is 45 litres,not 35.

rob1000
21-10-2009, 06:46 AM
Full tank capacity is 45 litres,not 35.

ahh ok, well regardless when i filled up i added exactly 35 litres which is what I based the mileage off. So either my fuel gauge is off a bit and showing empty when there's actually 10litres left or I'm letting it click off too early

SHU-ES1
21-10-2009, 10:04 AM
have you installed the light yet rob?

rob1000
21-10-2009, 10:15 AM
have you installed the light yet rob?

not yet gotto get to that. soon i hope. few other things i gotta do with it first. (timing belt, noisy clutch bearing etc)

Will get that light sorted before we go on a decent trip so i can test it out!

SHU-ES1
21-10-2009, 11:13 AM
i read that putting a vtec light, sucks current/voltage away from solenoid so vtec doesn't go as hard as it would without it? is there any electrical physics behind this theory?

rob1000
21-10-2009, 11:18 AM
i read that putting a vtec light, sucks current/voltage away from solenoid so vtec doesn't go as hard as it would without it? is there any electrical physics behind this theory?

Nah pretty sure thats not true. AFAIK there is simply a wire going from the ECU to the solenoid telling it to engage or not. It doesn't power the thing... someone correct me if im wrong.

Its similar to how you have a wire going from the head unit to a power aerial. COnnected up, broken off.

Edit: just been reading this http://www.asashop.org/autoinc/jan2005/techtips.htm

yeah so basically the solenoid is either on/off same as a starter motor solenoid i guess (pretty sure they work by having a little bridge which flicks on with current, off without). oil pressure is used to tell the ECU that the vtec solenoid should be turned on to enable VTEC. So in order to screw up the VTEC you would have to be interupting the 12v needed to turn on the solenoid. Someone else could probably explain that better or correct it :)

98vtir
21-10-2009, 12:08 PM
i read that putting a vtec light, sucks current/voltage away from solenoid so vtec doesn't go as hard as it would without it? is there any electrical physics behind this theory?

Is that similar to when the A/C is on the car is noticeably slower? But I'd think that even though the LED is 12v, it's such a low current it shouldn't be too bad. Not that I know much about electronics and such but when I chucked in LED indicators they blink like buggery now. Atleast x2 what they incandescent ones blink at.

rob1000
21-10-2009, 12:14 PM
But I'd think that even though the LED is 12v, it's such a low current it shouldn't be too bad

nah there's no worry about it, Its a solenoid so either ON or OFF its never half on because there isn't enough power :)

98vtir
21-10-2009, 12:42 PM
haha true, cool beans :)

SHU-ES1
21-10-2009, 01:04 PM
Is that similar to when the A/C is on the car is noticeably slower? But I'd think that even though the LED is 12v, it's such a low current it shouldn't be too bad. Not that I know much about electronics and such but when I chucked in LED indicators they blink like buggery now. Atleast x2 what they incandescent ones blink at.

i think that is due to the lower resistances in LEDs in comparison to normal halogens globes, hence the quicker blinking speed. i put them in yesterday for a bit, and they were blinking so fast - bit like a strobe light! haha.

twing
21-10-2009, 01:08 PM
according to your calculations, you're getting 5.61L/100km. that's is awesome! hehehe.. well done! and yes, i can keep it at 100km/hr without the light coming on. it's only when i'm at about 105-108km/hr thats when the light comes on regardless due to my revs being over 3.3krpm.

Great info!... Damn... 108kmh is still under 110kmh highway limit.
Should I choose low speed in 12v which save petrol but taking longer for syd-mel trip? Or should I choose 110 kmh speed in 16v, uses more petrol but faster to get to destination?

I will choose 110kmh :)... hang on, how about putting in vtec controller. Therefore you can set it to switch on after hitting 115kmh.

rob1000
21-10-2009, 01:17 PM
hang on, how about putting in vtec controller. Therefore you can set it to switch on after hitting 115kmh.

Would be great

thats actually what i originally wanted to do :D i think they are only like $80? Yeah you could set it to only come on after 110 or 115.

bah $5 led will do me i'll just drive slower. I remember reading somewhere too that in any car driving at 100 instead of 110 saves a heap of fuel can't remember how much it was and cbf googling :P Anyway, driving at 100 coupled with only 12 valves would save a fair bit imo

Edit: here's basically what i was thinking of...

Want to save an easy 12 -15%? You can if you drive at 100 km/h instead of 110 km/h. When you double your speed the drag or energy required to push you through the air goes up 4 times.
http://www.ecodriver.co.nz/ecodriver/tips.html

redefine
21-10-2009, 03:59 PM
ahh ok, well regardless when i filled up i added exactly 35 litres which is what I based the mileage off. So either my fuel gauge is off a bit and showing empty when there's actually 10litres left or I'm letting it click off too early

my fuel guage usually shows empty like 100km before it actually is :thumbsup:


i read that putting a vtec light, sucks current/voltage away from solenoid so vtec doesn't go as hard as it would without it? is there any electrical physics behind this theory?

nup. the light draws a little more current from the battery...but the solenoid still has the same current going through it. it takes 12v to engage and when it does it will be either on or off like people have said. vtec-e is exactly the same as normal vtec except different cam profiles to favour efficiency over power. if you want to know more search how vtec works on youtube....some awesome vids to explain it in more depth there :thumbsup: