GT Rulebook Amendments

[Tom Meyer]

How about this one 1966 Chevy 283/220. GT rated 233, Nova 233, Big cars 229, Chevelle 217 all different platforms but same engine specs. Tom

[CMcAllister]

Combinations where a simple carb/intake change changes the year of the engine?

'68 - '71 or even '73 Darts/Dusters with 340s?

Or is a different year spec engine all that is required to go to GT?

[Mike Pearson]

The way I interpret the rule is if the engine in your car is correct to run a specific super stock class then it cannot run GT. Some change would have to be done for it to be legal in GT. Carb change, Different heads etc.

[LE WILSON]

I agree with what Mike said. I have a 1964 Chevy ll with a 283, a natural K or L car in regular SS therefore can’t run that combo in GT/M or N any more. What’s unfortunate with that is the stick hp rating is 7 hp less in GT.

[J Gower]

Larry, NHRA just took 283-237 down to 230

[Tom Meyer]

NHRA just took 283-237 down to 230 This stick cars in a Chevy II only Autos is 233. Chevelle with a stick is still 227, Auto is 217. SS/J K L M is a 1# weight break, where do the GT classes go 1/2# breaks? Tom

[Ed McLawhorn Jr.]

Originally Posted by Tom Meyer

NHRA just took 283-237 down to 230 This stick cars in a Chevy II only Autos is 233. Chevelle with a stick is still 227, Auto is 217. SS/J K L M is a 1# weight break, where do the GT classes go 1/2# breaks? Tom

Tom, I believe GT/A starts at 6.00 and go 1/2 break all way to GT/Q at 14.00. 6th

[herbjr]

Originally Posted by CMcAllister

Combinations where a simple carb/intake change changes the year of the engine?

'68 - '71 or even '73 Darts/Dusters with 340s?

Or is a different year spec engine all that is required to go to GT?

a 68-71 340 is a totally different engine from a 72-73 340, they can run GT
if a 69 engine is in a 72 car

[CMcAllister]

Originally Posted by herbjr

a 68-71 340 is a totally different engine from a 72-73 340, they can run GT
if a 69 engine is in a 72 car

Correct. The 68-71s used different carbs on the same basic engine (mostly). My question was, will a simple carb change to something other than was used in the model year of car, i.e. a 68 Dart with a Thermoquad, make it acceptable for GT. I believe I got my answer.

Thanks.

[Paul Precht]

Originally Posted by CMcAllister

Correct. The 68-71s used different carbs on the same basic engine (mostly). My question was, will a simple carb change to something other than was used in the model year of car, i.e. a 68 Dart with a Thermoquad, make it acceptable for GT. I believe I got my answer.

Thanks.

71 340 should be legal in a 68-70 for GT.