GT clarification
 

I run a 66 327/275/307 combo in super stock. Can i run a 67 327/275/307 combo and run in GT class or for instance have to claim a 65 327/250/270 or a 65 327/300/285 combo to run in GT class? just a little confusion for me someone please explain
thanks jason

Re: GT clarification
 

jaf2021, many times, the GT rating and traditional (SS/HA, IA, etc) rating are different.

1967 Chevy 327/275, in GT, is rated:
295, OEM head, stick
299, OEM head, auto
300, replacement head, stick
304, replacement head, auto
So be sure to look out for this info when choosing an engine for GT purposes.

As far as an engine for GT, pretty much any motor is fair game, if it is corporately-correct (any Chevy engine in a Chevy, Buick, Olds, Pontiac, Cadilac, etc). Just be sure to use the GT rating when figuring legal Class(es) and weights. Youcould put a 2012 COPO motor in, if you wanted to. :)

Hope this answers your question.

Re: GT clarification
 

thanks mike i looked at the regular rating 275/307 instead of the gt rating 275/299 for 1967. The motor combo should be the same if i am correct(heads,carb#207). so all i would have to do is change my ss/ia to gt/e-g whichever weight i run. Is this correct?
thanks jason

Re: GT clarification
 

Yes. Shipping weight of '66 Nova, divided by 299 (or whichever heads/trans you're using) = whatever class. And, you can add or subtract 250 pounds from the shipping weight to adjust classes.

Re: GT clarification
 

so it seems that even though a replacement head may be better performance wise, using it taxes you in additional factored hp...therefore more weight?

Re: GT clarification
 

Yes. 5 hp in, say, GT/EA = 5 hp x 10 pound class = 50 more pounds over an OEM head.

Re: GT clarification
 

GT/FA weight for a FWD converted to RWD? What is the weight limit, 327, which would be a good model HP to claim

Re: GT clarification
 

hey mike, im sniffing at a GT 327ci auto/combo w/small valve an oem head, are the replacement heads for such getting used at all?

Re: GT clarification
 

trmnatr, GT/FA is a 10.50-10.99 pound class (shipping weight divided by NHRA rating of the engine). 10.50 x NHRA rating of the engine + 170 = minimum weight, with driver, across the scales. GT cars may adjust up or down 250 pounds from factory shipping weight. Stockers and traditional (non-GT) S/S care permitted ot run their natural class, up one, or down one. So, whereas, say, a '69 Camaro 427/425 that falls into SS/DA can run CA or EA, GT cars can run, sometimes, up to five different classes (GT/DA EA FA GA) though they may not be able to make the 'top' of the highest of those classes (might have to run 50 pounds heavy for the top of GT/DA) with the 250 pound rule.

Richie2, not sure. Many GT racers are going with later model, lower rated, efi small blocks (80's/90's 305's, etc). Which 327? Some run well with a '64-'66 327/250 combo, like Bob Cupp would run in SS/KA in a '65 Malibu in newer cars. Mike Walter runs well with a 327 like that in a '92 Firebird in GT/IA-JA Maybe he, or someone who runs one can chime in. I'm just a dumb, retired kid (is age 32 still a kid?) who ran FWD Stockers. LOL

Re: GT clarification
 

Mike and others:
I have a couple more questions about GT classes. Say my 67 Firebird was an original 6 cylinder car, what shipping weight would I claim if I wanted to run a later model Pontiac 400? What hood can you run in GT?
Also, can you claim a GT motor of the same year as the car? 67 car, with a 67 GT motor combo?
thanks
Ken