Bird-Of-Prey

iTrader: (23)

I'm thinking of buying a Comp cam that specs out at 581/588 224/228 @50 on a 114+4 LSA. This would be a great N/A or Nitrous cam but I'm concerned about it with a turbo. I'm going to be running a T6 flange T76 turbo with a 1.08 AR and shorty headers. I know that each and every cam on a turbo setup is different and should be speced according to the entire package. My thinking is that with shorty headers and being a T6 flange with a 1.08 AR the standard split cam should help spool the turbo and not hurt backpressure at all. I should have more than enough flow to accomidate this cam. However, I'm concerned about the advance built into the cam. The 114 LSA is fine but being a 114+4 that would put it on a 110 ICL. My understanding is that a 110 ICL would cause cylinder pressure to rise and increase my DCR. I'll be running stock heads for a while. Eventually going to go with #317's.

What cams are you guys running with what turbo setups?

Also what are your thoughts on this cam or running a standard split with my setup?

Jammer

iTrader: (1)

Om a fan of reverse split for street turbo applications..but that goes back to the days of Ed Curtis and J-Rod.

The good ol days..remember the cam threads!

~JOSHUA

iTrader: (92)

I'm running a cam that the Buick GN guys might relate to (close LSA.)

236/236 .580 .580 112 LSA

NicD

iTrader: (7)

A very nice custom cam at 230/224@.050 .592/.589 114 lsa 112 icl, that's all you get.

Ryan K

iTrader: (11)

Mine is a CamMotion Custom, its a 226/222 with .560 lift on a 115 lsa.

I like it...

Ryan K.

Rusted40

it seems like the reverse splits would matter more on engines with high backpressure?
I wonder how many people actually measure their backpressure.
unless you're copying a proven setup you can only hope to get it close
usually close is good enough

mdhmi

iTrader: (1)

I've had good results with an LPE GT2-3 cam on my TT LS1. The new LS6 motor has a custom reverse split cam. I figured if you're going to spend $2,500 on heads you might as well spend $400 more and get a combo specific cam.

Bird-Of-Prey

iTrader: (23)

Exactly! It's pretty much common knowledge that traditional split cams are more efficient and beneficial to a N/A motor. Reverse splits are more beneficial to a turbocharged motor that has log manifolds or cast exhaust manifolds. This is due to the exhaust being restrictive and not being able to expell all of the exhaust energy resulting in backpressure. SC and nitrous motors also benefit from traditional splits because they don't have any restriction in the exhaust such as the turbo itself. The more you push in, the more you need to get out. With tubular headers, T6 turbo and a large AR I think a traditional split would be more beneficial in my case.

I'm more so worried about the +4 advance built into the cam that would put it on a 110 ICL. Wouldn't this raise cylinder pressure and compression too high to use stock heads? If so, couldn't I just degree the cam or use an adjustable timing chain to retard the cam to 114 LSA 114 ICL straight up?