You must not have seen the rule that says...... if it doesn’t say you can do something.......then you can’t.
Basically, you start with a 100% stock car, and you can only change the things specifically listed.
This past September.......
1972 340 Demon(low cr, small valve heads)....... 12.46@108
A few years ago.......
73 360 Duster, 3.55’s, 3504lbs, 13.78@100(shows about 270hp)
