Correct GT class
 

What would be the correct GT class for my car? I'm currently running SS/I with the 327/275hp combo with a 207 q-jet. I believe with a 4GC it will be the 250hp combo. Thanks. ED


66 Chevy II

3120 lbs including driver

327 with 4GC carb

Re: Correct GT class
 

If you have Excel you can use my calculator to tell you what classes you can run. Just enter the shipping weight, factored HP and trans type and it will tell you the legal classes and appropriate weights.

Remember that the rulebook says that for GT classes you have to use the shipping weight for the body style with the largest available gas engine.

www.employees.org/~bhracing/gt_class_calculator_1p1.xls

If you don't have Excel I can run the numbers for you.

Re: Correct GT class
 

Bill,

I'm not on a computer now with excel. I can do it tommorow when I get home. Do you use the shipping weight of the car your claiming? A 66 never came with the 327/250hp combo. The 65 did. Do it calculate with the 65 car? Thanks.

Re: Correct GT class
 

Ed use the 66 weight.

Re: Correct GT class
 

Ed,
You need to change heads as well as the carb to make it a 1963 250 HP. 1.72 intake valve and smaller chamber in the 520 (250 HP) head. Also, it's 250 HP in S/S but 258 HP in GT.
I run GT/IA (12 lb/HP) @ 3266 minimum with that combo.
The 1965 250 HP uses your 275 HP head but it's factored to 260 HP. Maybe the Q-jet is worth the 15 HP. It's got to be close.

Re: Correct GT class
 

That's what I said, but it's factored to 260 HP in SS with the 041 heads or 265 HP using the World heads. I don't think 15 HP less and the bigger intake valve offsets the much smaller carb.
JMHO.