cubic inch limits

[66 lemans]

want to know if a 389 pontiac would fit in the small block class. want to run street race sb na next year with a 66 lemans.

[Brian Lohnes]

You should be OK with a Poncho 389 assuming it remains below 430ci.

[66 lemans]

thanks for the info. wanted to go this year but with the purchase of a new home with more and bigger garage and the distance to get to the first stop ended that idea. my money tree ran out.

[tsanchez]

MIne did too, still went so now its just a sappling

[66 lemans]

two months witout rain this summer. mine up and died.

[JeffMcKC]

Brian I believe they look at it as a de-stroked Big Block because of the heads available to it. Brain Rocks was Grandfathered in. Same as the FE engines. When I built mine I wanted to de stroke a BBC and run in the small block class, David said that was a no go, its more than the cubic inches in the engine. I would re-ask if there is a question on it.

[ksj2]

Brain Rocks?LOL. I didnt know BRIAN was grandfathered in.Yep, like Jeff said probly should ask for sure.

[JeffMcKC]

This is the was it was I may have changed.




Small-Block Naturally Aspirated, Small-Block Power-Adder, Big-Block Naturally Aspirated, and Big-Block Power-Adder. Naturally Aspirated classes may not use power-adders of any kind. Power-Adder classes may use nitrous, superchargers, turbochargers, propane injection, or any combination thereof. Small-Block classes are 430ci and below. Big-Block classes are 431ci and above, including Mopar Hemis, big-block Chevys, big-block Fords, or FE Fords of any displacement. Winners’ engines may be pumped to verify displacement.

Read more: http://www.hotrod.com/dragweek/2011/...#ixzz1kU0oU2FK

Read more: http://forums.hotrod.com/70/9012343/...#ixzz28Ql17Cwa

[squirrel]

looks pretty clear, small pontiacs are small blocks, big pontiacs are big blocks.

Which makes sense. It's a relatively small engine, which started life as a 287 in 1955

[66 lemans]

Mine will be a 40 over 389 with a stock stroke crank and pontiac heads. The block, crank, and heads are all original 1966 pontiac. Guess the best thing to do is email DF and see what he says. thanks for all the info. Hope to meet some of you in 2013.

[milner351]

Yes - confirm.

Carl's black and orange 55 that registered in DD but considered swapping to class racing - ran a 427 BBC,
less that 430, but a "big block" so what class does it fit in?

ANY FE Ford is a "big block" ?
they came from the factory as 352, 360, 390, 406, 410, 427, and 428

ANY "wide valve cover chevy" is a "big block" ?
396, 402, 427

So a pontiac 400 - which shares heads with a 455, is a big block too?

this does get confusing

[CDMBill]

Yes - confirm.

Carl's black and orange 55 that registered in DD but considered swapping to class racing - ran a 427 BBC,
less that 430, but a "big block" so what class does it fit in?

ANY FE Ford is a "big block" ?
they came from the factory as 352, 360, 390, 406, 410, 427, and 428

Yes

ANY "wide valve cover chevy" is a "big block" ?
396, 402, 427

Yes

So a pontiac 400 - which shares heads with a 455, is a big block too?

No, depends on actual displacement based on our reading of the rules and the last time it was addressed by DF (see Brian Rock rule Jeff mentions above).

this does get confusing

Yes it does.

[milner351]

Thanks for the clarification Bill.

I know pumping takes time - but it seems that's really the only fair way to handle it.

I don't think it's fair to put a 396 chevy, 390 Ford, 389 or 400 pontiac, etc in with 500+ cubic inch power plants.... but I don't make the rules.

[JeffMcKC]

I would love to have built a BIG BORE, short stroke BBC for the class at 430 CID

[Lilracr]

I would love to have built a BIG BORE, short stroke BBC for the class at 430 CID

Jeff, why do you think it would be faster than your SBC combo? The BBC even under the small inch rules would be at a weight disadvantage. With the ability to run aftermarket heads the weight would be more of a factory than the bore/stroke/big head combination. Yes, No?