jack90

I am picking up a 90 Iroc with the 350tpi and shorty headers and o/r y back to a flowmaster 1 chamber...It also has a airfoil and adjustable fuel pressure regulator and a t-56 6speed swap done to it....I am trying to figure out a cam for it...What do you guys think would be best for it...It is going to be a driver and every now and the might make a few runs with it...Thanks for all the help...

TKOPerformance

If it's a '90 it has a roller cam, so you can run a stock replacement style roller, which is good news because that will save you some coin. You can't get too crazy with the cam unless you are going to have a PROM (commonly called a chip) made for the car. The S/D cars will only tolerate about a 5-10% increase in airflow before they start to act strangely. The real key to this question is what heads does the car have? If they are L98s I will give you one recommendation. If not it's going to be another one. Post back and let me know.

jack90

Yeah it has the L98 heads on it....I can get a chip done for it as that is not a problem....

TKOPerformance

I'd look for a cam with about .488 -.500" lift (a bit more on the exhaust, a bit less on the intake, something like .498/.509, etc.), a 112 degree LSA, and like 215 degrees of duration at .050" lift. Comp Cams makes a great cam that fills this bill under grind number CS-XR264HR-12. This will work with a factory roller block, and you can reuse your stock lifters (as long as they are in good shape, or for about $100 you can get new ones). You may need a bronze distributor gear with this cam, and you may need to swap for the recommended valvesprings, but otherwise it is a direct bolt in. This should get you close to 350-360HP with no other changes (other than that PROM we mentioned). Anything more and the stock TPI unit is going to hinder power production because you are going to have to raise the RPM ceiling past 5,500 RPM, and the TPI just doesn't flow well above that RPM.