NHRA Stock/Super Stock Classification

[Bill Harris]

Bruno, the C8OE-J heads are the 2BBL heads and have a larger combustion chamber than the 4BBL heads. The 4BBL engine was 10:1 while the 2BBL was 9:1 which is why the chambers are larger. So, no, you can't use them on the 302/230 engine in S/S. The right heads are either C7OE-C or C8OE-F.

There are two aftermarket heads approved for the engine. One is a AFR #1299/165 and the other is an Canfield #18350. The S/S HP using the aftermarket heads is 230 while it it 220 if using the Ford heads.

[Jeff Lee]

I'm with Terry and I've looked at this as a GT / SS option for a Maverick. Go with the 1968 Mercury 302. Class break down is the same as the '68 Ford 302 4bbl

[Wisman Racing]

I am putting my '69 Camaro into super stock next year. I just need to know if IHRA's horsepower factor is the same as nhra's, and if I were to goto super stock production how do i find a combination to use?

[Mike Carr]

IHRA Super Stock Production is pounds per cubic inch. Weight of the car with driver, divided by the cubic inch of the engine = the class you will run. If it fits into, say, SS/PAA-1 (7 pound class) with a 427, you would weigh 2,989 pounds.

In horsepower to weight categories, IHRA generally mirrors the NHRA ratings, but not always. As an example, the 1990's LT-1 in a Camaro/Firebird for SS/IA, it's rated 279 in NHRA and still at 275 in IHRA.

All the IHRA info, including people to contact regarding a question, can be found here.

http://www.ihra.com/competition/index.php

[Ryck Campbell]

Bruno,

Actually there is no such thing as a "natural" class in NHRA SS/GT. Using the 12.98 weight break, the car's shipping weight is 2726. From there you can subtract a maximum of 250 pounds or add a maximum of 250 pounds to calculate what classes the car can fall in. With the maximum removal of 250 pounds the car won't make the top of GT/F(A) with the 230 hp engine but the car could:

run heavy in F @ 2670
G @ 2700
H @ 2815
I @ 2930
J @ 3045

using the 220 HP engine in would be:
heavy in G @ 2670
H @ 2700
I @ 2810
J @ 2920
K @ 3030
L @ 3140

This is using the data available as of today, 12/2/2010. Hope this clears things up a little.

[1299]

so if t have a 83 grand prix (shiping w-3300) with a 327 nhra rated at 299
i can add 250 to it?
so 3550/299=11.87 which is gt/h or remove 250 and get 3050/299=gt/e
so i can run from e-h????

[Ryck Campbell]

Yes, a 1983 Grand Prix Coupe 2 door Brougham's shipping weight is 3300. With a 327 rerated to 299 hp the car would run:

heavy in E @ 3220
F @ 3305
G @ 3455
H @ 3605