Thread: Activating VVL for boost

hell ya!

Yeah I get what your saying, I just wanted to try lending a hand I guess. Didn't think about that. Since its just a stock roller rocker the timing had to be lowered considerably because it was knocking so easy. And the ve is stronger internally than my roller. Good point though. Thanks Vadim for the enlightenment. If that's even a real word.

No worries mate, I really made the same mistake and could not for the life of me figure out why I was knocking so much. Everyone always said VE's had superior knock protection, thus I figured a 10.1 or even 9.5 boost tune would work fine. Tried them, had knock and poor performance, then started researching and changing how I think.

You really can't tune a VE like you tune a DE, you have to tune a VE like two different engines in one. Part of your map needs to be before VVL kicks on, and another part after VVL kicks in and parts fairly different from each other .

great advice Vadim....

It makes sense I always thought of a ve that way, just didn't think of it at that time. I wish I could finish my ve swap so I can tune it and help others with base tunes.

Just throwing it out there, from what I learned talking to JWT about a new tune for my car...

They have seen better results leaving the exhaust cam unhooked, because when it switches to the high cam, the overlap is not tight enough to build the proper cylinder pressures.

i would not feel right about revving to 7k+ on low lobes.

Thats why I didn't even bother with it, until we get better cam development, I'll stay on my DE block

well pleanty of guys have had good results with their simple ve-t setups, im hoping i do too. jwt might know ALOT about tuning and stuff but im just not going to take their word for it lol.

now if you think about it, didnt the actual VET not use vvl on the exhaust side? im sure those cams were designed to be used like that though. i dont really know alot about the VET

Thats how it was explained to me, unless you can get a hold of a VET exhaust cam, the 20VE exhaust cam isn't the greatest.

Its easy to understand though, I can't say myself that I have seen the difference, but with it being JWT, I believe it. He said there was a 20-30 hp difference on big turbo cars.


Too much overlap = less time to build cylinder pressure = less power.


My buddy at school runs N/a cams on his k-series just for the tighter overlap.