Thread: Jwt S4 cams or vvl head ?

S4's are awesome on a turbo'd de.

I ran them both with my t25, t28, and t3 60 trim turbo and made great power.

Now im running C2's with an even larger turbo. Should be fun.

VVL with turbo are overrated. If your setup isnt just right it wont make good power. Ive seen a lot of turbo'd VE's that my DE outshined and this was with similar sized turbos and similar boost levels.

Again it all depends. Your cheapest and easiest route is to just throw the cams in especially if you plan to use the t2 turbo.

C2s sound fun.

Stratton.

I cant wait to hear it idle with the 6765 large t4 turbine housing open 3" downpipe dumping at the bottom of the bay. I loved the way the s4's idled with the same open downpipe at the bottom of the bay with my 60 trim t3. Id imagine the C2's are gonna make it sound like dont f'n mess with me mean. Cant wait. lol

I've been wanting to run a ve head. I was thinking more flow = more power, right? Now I'm confused...

Keep it simple and keep the De head. That's what I'd do. You'll have enough problems with the turbo and tuning. If you decide later down the road that you want something more advanced then upgrade. You can always sell the cams they seem to hold their value pretty nice.

I say you install that damn downpipe.

not always. It depends on cam profiles, turbo sizes, and so on. One setup may seem good but not have good results and another that simpler will work best. This is why the s4 cams on a de are soo popular because they give great results. The DE head might not flow as good as the VE head but you can make up for most of that with s4 cams. Again would i ever run C2's on even a small frame t3 say 50 or 60 trim? No because the C2's have way too much overlap and duration for smaller turbos. But for larger frame turbos you want to have a large lift and as big of duration as you can to make the most of it and you better have a good flowing turbine side to keep backpressure down that way heat does not stay in the cylinders.

This is why people run into soo many problems overboosting a t25 turbo or t28 turbo. The t2 can only flow soo much and backpressure starts to get very high but higher backpressures between the exhaust valves and turbine do help spool time but will hurt topend.

Again there are soo many variables.

With the turbo im using the C2's should be an awesome cam well matched with the turbo and should make great power and make power well up into the 8500-9000 range without falling off.

Yeah I love my Greddy turbo and S4's. It gave me the results in my sig on 20lbs with conservative timing.

Dont you also have to notch the pistons to keep them from hitting the valves when you put a VE head on a DE? Or is it the other way around?

I would move to the .86 housing along with the vvl head.

The reason why i asked this question is because i do have both setups s4 and a vvl head...so with the turbo i have now, s4's will produce more power then the vvl head at 20 psi? Is there a way that i can unleash better exhaust flow from the vvl or is it the 20v cams?