i have an 85 corvette sbc with the stock fordged pistons. Everything i've read says 9-1 with the 76cc head and a steel shim head gasket.


i'm doing a topend rebuild and have a set of ported dart iron eagles (180 CC runner) with 64cc combustion chambers. i want this to run on 93 premium. I also plan to spray it with a 100 HP kit. I was going to use the CC nitrous grind 224-236 on a 113 LSA. But now i'm thinking i might have problems with detonation ? the car weighs 3440 has 2500 stall 700r-4 with 3.07 gears. I have an GM HEI and stealth weiand intake with 750 vac sec carb. 1-3/4 headers with 2.5" dual ex.


using the D...something program that you guys use what cam and head gasket thickness do you recommend?

thanks
Mike

almost forgot. 6K is as high as i want to spin it.

I would not bother with a nitrous cam for only a 100 HP shot. It's just not needed at that power level.

Most factory small blocks have a factory deck height of right about .025". A Felpro #1094 has a compressed thickness of .015" which would give you a total deck height of .040" - perfect for detonation resistance. Your compression ratio with a -6cc flat top piston and a 64cc head would be right at 10.0:1.

If you DO in fact have a flat top piston and 64cc heads then IMO the following cam would work well:

Comp XE274. 274*I/286*E advertised duration, 230*I/236*E duration @ .050, .490"I/.490"E lift, 110* LSA, 106* ICL. Makes a dynamic compression ratio of 8.1:1. That's pushing it just a hair, but you should be fine with pump 93 octane and the Dart combustion chamber.

As an extra safety measure when running N2O you could install separate fuel supply for the nitrous. A 2 gallon fuel cell in the trunk with 110 octane in it and a small electric fuel pump would do the trick.

Just my opinion.

PS. The Nitrous HP grind you mentioned would have exactly the same IVC timing as the XE274 I mentioned so IMO they would have the same dynamic compression ratio. EXCEPT the XE274 would be significantly stronger when not running on the bottle and the Nitrous cam should have a more docile idle.