Board logo

4AGE 20v VVT
Worzey - 27/5/09 at 09:29 PM

Can anyone suggest the best possible RPM to engage the VVT on a 4AGE 20v engine?

I'm running an Omex 500 ECU and think it can be configured.

Is 4000 RPM about right?


Steve Hignett - 27/5/09 at 10:31 PM

Just searched google (for you), and the top three answer all seemed to reflect the same sort of thing...

http://www.billzilla.org/vvtvtec.htm


tootall - 27/5/09 at 10:58 PM

well u will be getting engine mapped on rolers ?? if so u need to map it off vvc then mapp on vvc and compair power run charts over lay them and compair ther will be a point were the bhp line crosses that is the point it should switch.
but it will be differnet on half throttle etc so its a tricky one realy

i built a mk1 mr2 for a customer with a 20v black top 4age and its a lovely engine that will go to 8500 all day long infact it feels like it is still making power when hitting the limiter and thats on standard ecu just with a different box over throtle bodys is a bit larger standard one does restrict it alot

[Edited on 27/5/09 by tootall]


rick q - 27/5/09 at 11:28 PM

Standard, I believe the VVT on a Silvertop switches at 4500 rpm. I'm running a Haltech and mild cams on mine and found it best to change at 2500rpm.

Some even have it shutting off again at high rpm though I don't understand that one.

The description tootall gave is the way to fly, switching at the point the two torque lines cross.


Phil Bradley - 28/5/09 at 11:55 AM

Hi
Mine comes in at 1850 but, I have wild cams and other trick bits in my Blacktop.

My engine comes from an old Class B racer - no longer permitted to race but I have it on good authority that she makes 115KW's on the wheels. The intake cam has been locked to prevent it from "closing"all the way, when the VVT kicks in, she opens up really wild. I'm running a Microtech LT10 management system.

If memory serves, the guys down here have the VVT switching on from 2000 to 2500.


Cheers,
Phil Rescued attachment Picture 367.jpg
Rescued attachment Picture 367.jpg


nz_climber - 29/5/09 at 08:05 AM

Like has been said where the two torque curves cross is best, so might take a bit of playing with on a dyno, but only an extra couple of power runs. many people lower it on a standard engine, but just end up losing mid range torque.. (but if you got a cap on backwards then its great!!)