Vtec

[KGod86]

i keep hearing people say thier vtec isnt kicking in, well my question is how do i tell if mine is kicking in?

[2poor2tune]

you can hear it. depending on when it is set in your rpm,s. what car do you have? year, modle, make

[FrodoGT]

On SOHC its a little harder to tell than a DOHC, but its still there..you should feel a slight drop in the powerband and then the vtec will kick in and youll feel it pull harder. Also, if you have an oil pressure guage youll notice oil pressure drop slightly when it comes on, and, if you connect a light bulb to the wire running to the solenoid and a ground, when vtec engages it will light up.

[2poor2tune]

yep DOHC screems like no other. sohc not so much but still easy to tell. im guessing its sohc since someone with a dohc motor with vtec knows what they have so it should be anywhere from 5700 to 7000 rpm's im am pretty sure

[FrodoGT]

Yeah totally forgot to mention, on a DOHC it is supposed to engage at 5k rpm. I think SOHC is a little lower like 4700 or 4500, I dont remember..my frined has a d16z6.

[2poor2tune]

are you sure. my friends stock d16y8 kicks in at 6200 or somthin real close to that. and my other friend got a b16 and it hits at 5200 but its chipped. so i dont know. but thanks again for the help with the wiring frodo. you are a life saver

[FrodoGT]

Yeah, except that the sohc redline is like 7200, so that would leave a very small vtec range. I did a little reading and I found that I may even be a little high with the numbers..Ive seen 4400 as well as 4200..

[TheSilentChamber]

z6 is in the 45-5000 range, y8 is in the 54-5700 range. It varys from generation to generation, on sohc and dohc.

[mellowboy]

If I remember correctly my b16a kicked in at 4700.

[PhReAzE]

Originally Posted by mellowboy

If I remember correctly my b16a kicked in at 4700.

mine does too pr3-j00 ecu

[Moppie]

wwwiiiiiizzzzzzzzzzzzzzzzzzzzzzzzzzzzZZZZZ-----BAAAAHHHHhhhhhhhhhhhhhhh

Thats VTEC.


The old B16a with its orignal ECU will change anywhere between 4,700 and I think 5,200? Its been a while since I drove one.
Basicly it will hold off the change if your useing a light throttle opening, but will engage earlier if your useing full throttle.
Like wise changing when slowing down. If you lift off from a light throttle it will change at high rpm then if you lift from full throttle.
Its designed to stop you getting stuck in small flat spot if your driving "hard"

The later model B16s used differnt cams, and the change points a few hundred rpm higher up.

[civic_boy91]

if its not working you motor will feel like crap when you try and redline it...it will seem like forever to get to redline...if its not working you should know.

[FrodoGT]

Yeah, I hear that..mine actually wont even redline, I tried..took like 10 secs to get to 7600 and at about that it cut out for a second..just couldnt do it. But I was throwing a light so it didnt help.

[mellowboy]

Originally Posted by FrodoGT

But I was throwing a light so it didnt help.

Did you figure out the problem? Another thing I like to add is that sometimes your vtec will engaged lightly or not engaged at all due to low oil.

[4G4D Store]

Another thing that might be happening is if your ecu is throwing a code, I doubt it will kick in the vtec, also was your engine warmed up?? I've heard somewhere that if your engine isn't warm it won't engage vtec either.