Having previously owned an MR2 turbo, I obviously know nothing at all about vtec. So, when does vtec kick in on a prelude? When I test drove a demo before I bought mine, I could feel the pull at 5k rpm or something. Is that the right rpm when vtec kicks in?

 

5400~5500RPM with WOT.. Otherwise it will slowing come on around 6k rpm.

 

Mine kicks in at 5k in my 4th gen.

 

I swear mine is at 5k (4g).. I think someone said the 5g ludes are at 5,200?

MMM MR2 Turbo, Awesome Car! What happended to it?

 

5g ludes are at 5,400 (assuming wide open throttle). The actual engagment point depends on several factors such as throttle position, engine temperature and a few other sensors I don't remember right now.

 

Yea, it kicks in about 5400-5500 rpms, unless if you have a vtec controller


[Modified by prelude1897, 5:41 PM 6/9/2001]

 

WHen your car is cold and you drive it, Ive been told that it wont kick in...

I wouldnt know because I would never rape my car like that...

 

With the digital Temp gauges that the 4g preludes have, you have to wait till the first big bar lights up, then it will engage..

Spyder.. Vtec pretty much engages at a certain RPM and thats it, if you accellerate slow onto hi cam, it will still sound the same as low cam, but the HI cam is engaged..

Reasons VTEC won't engage:
Cold operating temperature......Low oil level......Not enough RPMs =~)

 

Then perhaps it's different on a Civic EX. Typical civic engagement point is 4400 RPM, but I have had it engage anywhere within the 4000-5000 range. RPM is not the only factor, it just uses a preset RPM as a reference point (generic good setting), and the ECU will move from that reference point as it sees fit according to the data it is receiving from its sensors. If you read some info and documentation on ECU's and VTEC controllers and talk to guys who tune V-AFC's (not people who have HAD their cars tuned, but the people that actually tune them), you will find that the point DOES vary.

 

hum, thats odd, mine engages at 5k, yes 5,000rpms my tach reads everytime, no matter what..

 

hmm...maybe I unknowingly have an engine with the new VTEC-i Honda's working on... I WISH!

 

HONDA318x, mine kicks in at 5000-5100 on my tach everytime too. And i have a 5g lude. All i really have are cams, headers, intake, and gears. My vtec has always been around 5k

 

the H22A stocked Preludes have a predetermined x-over point unlike all the other VTEC motors due to emissions. to meet LEV standards for california, the emissions must corellate to a standard by rpm's... if VTEC engaged lower, it would put out too many hydrocarbons at a certain rpm for CARB to accept as an LEV, so the VTEC point was raised. if you ever see a dyno chart on the 5th gen, you'll see that power drops off then picks back up at the crossover due to the low cam being engaged longer than it should be.

 

Yeah I could swear mine kicks in at exactly 5k rpm at WOT too.

 

Has anyone dyno tuned there car with a different Vtec point using a Vtec controller? If the power drops off a little before Vtec engages, why not lower the Vtec point?

 

If thats true, then Americans are missing out on Hondas true engineering...

 

it is true... but that's why many of us install VTEC controllers