[ponyakr]

Looked up some numbers.

GT/MA is a 12 lbs/hp class. The '77 350 has an NHRA hp factor of 250 for GT.

So, 12 x 250 = 3000. I think 170lbs has to be added to allow for driver weight. So, total weight, with driver, is 3170 minimum. Very doable.

The later model 400 engines have a factor of around 290. So, 12 x 290 = 3480. That means that with a 400, the car & driver would have to weigh at least 3650.

So, 3650 - 3170 = 480. That means that a 400 powered GT/MA would have be 480 lbs heavier than a 350 powered car.

I know that Mike Morgan has run quick with a '77 350 Bird, and Bill Rink has run quick with his '74 350 GTO. So, I assume that either a 350 or 400 combo would work. The 400 car will just have to be heavier, to run GT/MA.

Carroll Warling ran good, and even held the nat record for awhile, with his 400 powered '74 Lemans/GA. So, he proved that a heavier 400 powered combo can work.