SBC engine rules...

[Dirtman29]

Im wanting to move up to a local "pure stock" division for next season and engine rules are 9:1 max compression, OEM cast iron exhaust manifolds, 2 1/2" max exhaust diameter, all cast iron parts, any OEM carb, must pull 17" of vacuum at 1000 RPMs, hyd cams ONLY...any ideas where to begin? I have a mild built 355, OEM looking .030 pistons, mild street performance cam, the rest is a completely stock bottom end. And it'll be in a 3500# car. Any ideas what OEM heads to use, a better carb than a Qjet, decent OEM exhaust manifolds...any help appreciated.

[powerslide]

does it list part numbers on legal heads?

[stock car driver]

3310 holley vacumn secondary barrel

vortec heads 906 castings

ram horn exh manifolds are only ones that come in 2.5 dia so sounds like rules are written to allow them

high rise cast iron intake often called bowtie or z28.. have to drill vortec heads to bolt it up, use the gaskets made for the mismatch and it will be fine.

you will likely need a dish piston to keep compression 9-1, which is fine, they are lighter and help combustion chamber efficiency. I would buy je gas ported pistons.

[Dirtman29]

Must run a stock OEM carb & no ram horns allowed. Looks like any straight plug cast iron head is allowed.

[powerslide]

Vortec if legal are good like Jeff mentioned. Call the tech man and ask him before you sink a bunch of money into them. Most pure stock classes around here are open chamber type heads, no double humps or vortec's.

[stock car driver]

Must run a stock OEM carb & no ram horns allowed. Looks like any straight plug cast iron head is allowed.

3310 is a factory oem carb. google it. it came on a early chevelle or something, I don't remember its been years since I argued with a tech about it being oem.

they required me to get the exact one which I think was a 3310-2 -2 is type of choke it had I think. of course they changed the rules a week after I got the correct carb.

[Dirtman29]

Thanks for the replies, Ill have to check that carb out. Most guys are running Q-jets.

[stock car driver]

Q jets even built to the most exacting best oval track capabilities aren't that smooth on the track. I would use a single feed holley 600 before I used a q jet personally and there is no doubt they came oem on a lot of vehicles..

[let-r-eat]

An 800 spread bore holley came stock also.

[Dirtmod13]

Yep, I had a '68 impala with a 327 (not an ss) that came with a stock Holley carb. Power glide trans. Maybe you can look that up to find a carb number.

[Dirtman29]

Rules say NO holleys, says any "OEM" carb allowed.

[TBRE]

Vortecs are straight plug, and if allowed are DEFINITELY the way to go.
We have cams ground for those rules, and lifters that don' t hydraulic, Call Liz @ 601-847-4744