SCCA B Production Corvette

[Peter M.]

Anyone recall the specifications of the old A, B, C, and D production classes for the 60's ? I remember many of the famous Corvette race wins were in these classes thru 1966 but can not find the original specifcation that made up each class. What class did Penske's 1966 427 Coupe run ?

[Duke W.]

Re: SCCA B Production Corvette

SCCA has a set of General Competition Rules that provides the basic guidelines for production and other classes. Back in the fifties and early sixties production cars were close to "showroom stock". For example, you could run open exhaust, but had to retain the OE manfolds. You could remove bumpers and exterior trim. Convertibles could run with cutdown "windscreens". Up until about 1965 you could not "remove metal from the heads". Stock cams had to be used but they could be "reground".

Obviously these rules led to a lot of fenagaling and politicing and left a lot of gray areas. It was a constant battle between interests from this marque vs. that marque looking for an advantage or a break. For example, to be classified as a production car the "manufacturer" had to produce at least 100 examples annually. Shelby was a "manufacturer", so he only needed to build 100 Cobras, and when they wanted to modify the Cobra for more performance Shelby just made Weber carburetors, headers, and other modifications "factory options". Chevrolet obviously couldn't do this within the engineering standards and production release system that the Corvette had to live in, however, if Duntov had managed to get management approval to build the 125 GS models he would have been able to secure both FIA GT and SCCA "production car" status, and history would be a lot different.

Series built sports cars were classified in production classes based on SCCA's determination of their performance potential. I don't think there was a specific set of "rules" for each car, but there were probably "directives" or something similar to clarify specific issues as a result of things like protests.

Early Corvettes were classified CP, and the 283 models were "upgraded" to BP, as were the 327 models beginning in '62 upgraded to AP, but then "downgraded" to BP when the big blocks came along, which were classified AP.

Penske's 1966 Corvette Coupe was Chevrolet's "backdoor" engineering development car for the L-88 components and Penske only campaigned it in FIA events, which allowed more liberal modifications as long as the factory "homologated" them with the appropriate paperwork - like headlights under plastic covers and cold air induction hoods. I don't know if anyone has a set of the 1966 Corvette homologation papers, but they would be very interesting reading.

I have a copy of the Cosworth Vega FIA homologation papers, which were submitted to homologate the CV for the FIA Group 4 under two liter class, but the effort was stillborn.

A complete history of SCCA production rules would probably require a book lengthier than Manchester's "Rise and Fall of the Roman Empire". A history of the FIA GT rules and shenanigans would probably be twice the length.

Duke

[Jerry G.]

Re: SCCA B Production Corvette

Penskes 1966 would have run A/P since it was a BB( Very early L88). It also ran in FIA/GT class. I own a B/P Corvette racecar that was raced by Ed lowthar in the 60s.I have an extensive library of early SCCA and FIA rules from the period, which I use for race car restoration. If your thinking of running in vintage racing however you will need to decide which vintage group you will run with because there is an array of current club rules that reflect many variation and current allowed modifications which are different from period correct SCCA or FIA rules. There is really no one standard to prepair a vintage car to if you want to be competivitve and legal in multiple groups. I'd be happy to discuss with you. Jerry

[Michael H.]

Shenanigans and Rules

Duke,

Shenanigans is a great choice of words. Would be a great title for a book on the subject. I still have many of the "funny factory parts" that were used in A/P and Trans-Am years back. Quite inventive those boys in the back room at GM were! I think Yunick was one of the leaders in "funny parts" though.

Kinda reminds me of the Nascar guys and their shenanigans.

[Dick W.]

Re: Shenanigans and Rules

Michael, I emember when Smokey took the Z-28 to Riverside to run in the Mission Bell 250? They ran the car through tech, gave him a very extensive list of rules violations, told him when he got that list done they would give him another. He invented the book on creative rule interpatation. Even more so than old Doc McCagh

[Mike M.]

Re: Shenanigans and Rules

creative rule interprtation is akin to sleepin at the foot of the cross. mikie

[Michael H.]

Re: Shenanigans and Rules

Dick,

Sounds so typical of anything Yunick was involved in, especially with that Camaro adventure. Incredible list of excellent stories about his problems going through tech at almost any event, and most are true. His theory was, if the rules didn't specifically say "ya couldn't do it, it must be ok to do it".

Yes, I've heard some pretty bizarre stories about that Doc too. Heard he was trying to figure out a way to hide a nitrous bottle in his underwear because the tech guys found the last one that was hidden inside the fuel tank.

[Joseph T.]

Re: Shenanigans and Rules

I was reading today that Smokey built two prototype 427's out of 4 inch small blocks..and this was about 1957...just prior to his moving to Ford.

Does this sound right?

Joe

[Michael H.]

Re: Shenanigans and Rules

I suppose anything is possible but those early blocks would have needed a 4.250" stroke C/S to come up with 427 inches with a 4" bore dim. Highly unlikely but when Yunick's involved, never say never I suppose. Lot of hand grinding on the block would have been required.

[Joseph T.]

Re: Shenanigans and Rules

Mike

I recently purchased the Smokey Yunick life story book written by Smokey. It is a fantastic read and a close insight to the players at NASCAR, Indy and the auto manufacturers, his inventions and much more.

An absolute must read for any car guy, businessman, entrepeneur etc..

Joe

[Michael H.]

Re: Shenanigans and Rules

A good friend, Tom, that just happens to live a block away from me now, worked for Yunick for a few years so we talk about him often. He has many good (and bad) memories of those days and many good stories.