Hi,
I was just wondering if someone knows the exact behavour of VTEC. On H22A does VTEC kick only whe the engine hiths 4000rpms? or it kicks when you floor the accelerator as well?
Thanks for any info.

 

a stock h22 does not have vtec at 4000 rpms that i kow of, unless you have a program tht i have never heard of, and it odes not have anything to do with mashin the gas, it is set at a certain rpm

 

Yes, the gas pedal does has to be pushed somewhat. you could be crusing in VTEC RPM area, but not be using VTEC. but if you press the pedal farther down it should go in to VTEC. Also i think VTEC on an h22 stock is 5.5k RPM , unless you have some sort of chipped ECU.

 

You can mash on the pedal all you want, but unless you're at the right RPM, have the correct oil pressure levels, you won't go into VTEC... At 4,000 RPM? I wanna see the gas mileage on that car...

 

i know what VTEC stands for, but is there a noticeable difference in power. I can hear the VTEC kick in, but i don't feel it.

 

do you have dohc or sohc?

either one you are not really going to 'FEEL' vtec unless you have a more aggressive cam when it engages. You will feel power thru-out the whole powerband rather than some normal motor that runs out of power at lower RPM's.

you will however beable to rev more in the power band, and it runs off a differerent, higher and agressive cam lobe for higher RPM's producing more power throughout the whole power band.

HTH

 

actually I have both sohc and dohc, and on both of them i can't feel VTEC. Just wanted to know what everyone is talking about....i just hear it. I installed CAI on both and i can definately hear it cuz it's louder, but still i can't feel it. Maybe i just bought cars that don't have feelable VTEC.

 

Mine is set at 5700rpm. VTEC isn't like a turbo or anything. You need something other than a stock cam to "feel" the crossover. Also, lowering the crossover point usually gives you a "feeling", but when it's higher it's smoother when changing.

 

When I said at 4000rpms, I was only guessing. I don't have h22 yet, but am planning to do the swap myself. VTEC is new technology to me, so I just wanted to find out some more info on it. Someone said something about gas mileage if vtec were to kick at 4000rpms. Was that bad? And what is the torque at low rpms then? If vtec were only used at 5500 and above basicly you have a regular 200hp engine at lower rpms, correct?
Thanks for any input

 

If your VTEC was set at 4000 rpms, you'd be on the hwy cruising at 70 mph, in VTEC the whole time... Setting your VTEC too low will cause you to lose power up top as well, depending on your setup...

 

You need more mods. What kind of cars do you have again?

 

unplug your VTEC solinoid, go for a drive - then you will know...

t..

 

i have a 96 honda accord ex 4 cyl/vtec

also a 92 w/gsr

 

both those cars dont have real vtec
the gsr has an older b series motor (b17 i belive) but the cam isnt as agressive
if your ever in tucson ill let you hear vtec mine screams like a virgin.

 

heh, welcome to the new millenmium.
VTEC's been around for 14 years now, Japanese born in 1989.

Ok, depending on your engine setup...im assuming your engine is stock, so the factory VTEC crossover point should be just right, unless you've changed your camshafts to Type-R or somthing more aggressive. If not the VTEC point shouldn't be changed....you won't benefit from it with stock cams.

Lets say you have an Integra-R engine. The factory vtec crossover point is 5700rpm. Now if you lower it to 4000rpm (which is a damn joke) you're gonna hurt the powerband (actually until you get over the 5500rpm-ish point) and just waste gas infact. A VTEC ecu has 2 fuel & 2 timing maps, each pair of maps represents each instance of vtec, before-vtec crossover and while in-vtec. Now, once you kick on vtec at 4000rpm the more aggressive fuel/timing maps will kick on as well....dumping more fuel/timing; which is meant for 5700rpm and up to redline.

So, that's why it's kinda bad. I mean, it doesn't hurt your engine, but it will hurt performance. Now, if you set vtec up higher than the 5700rpm point.....lets say about 6200rpm, you'll notice the bump up in power once it kicks on. With stock cams (depending on which stock cams you have, btw, auto dohc vtec cams are a sick sick joke), and a stock ecu the crossover should be rather smooth, and you won't really feel it, since honda put the crossover point at its most perfect point.

 

Thanks Katman,
Now I understand more how vtec works...just a good thing to know before I start swapping my engine.

 

yesh..

 

The VTEC point on my 93 H22 Vtec (stock prelude) is 4850rpm. Of course that's not what the inaccurate tach shows

Aaron.

 

hahaha