What cam should i get for my 355 buildup

4 bolt 350 block rollor block
8.5:1 - 9:1 compression
forged internals
ported stock L98 heads
superram intake
150 shot NOS plate
25lb injectors
twin TO3's intercooled
stock 91' ecm
3.73 rearend
stock torque converter for now


Not sure of how much boost im going to run, but this must be streetable and run on pump gas.

somthing with a long exhaust duration... all the volume created by those power adders will need a long time to get out of the combustion chamber. I think theres somthing you do with the LDA to help increase exhaust velocity, but I dont rememeber what it is.

I'd go against that long exh duration, especially if you're building the engine more for turbo use, than NOS use. The T03's aren't the largest turbos, and will have fairly significant backpressure (on the order of 1x to 2x boost pressure).

Assuming your cylinders don't blow down 100%, you will always have more pressure in the cylinder than the intake port *until* the piston starts moving down again. A large exhaust duration will keep the cylinder at the exhaust pressure, causing reversion at the beginning of the intake cycle, so many turbo folks are using single or reverse duration cams (with intake more than exhaust duration).

Think of what is more important for you, and the trade-offs. Do you want better horsepower on the spray? Go with larger exhaust duration, but don't forget the huge restriction a turbo is (compared to free flowing headers). FIgure out the HP loss with the various trade-offs. I'm not a nitrous guy, but find out how badly less duration will hurt your on the juice performance if you run a more turbo-specific cam. Hell - try things out. Custom cams aren't terribly expensive compared to many of the other engine parts, so you can always change things down the road.

I'm running a Nitrous HP cam from Comp Cams and it works great.. That doesn't mean I wouldn't pick up more with a custom cam or something like that, but it seems to be working good so far..

Reason I'm running it is because I had my nitrous kit before I installed the twin T3's..

If you have to buy a new cam, I'd get something custom ground..

Cheers,