I did a fair amount of back cut testing on Brads heads.
They didn’t respond well to a long back cut.

Here is a close look at some of the ones I did for Brad way back when.

4 angles, longer top angle, bottom angle blended into bowl, no pronounced edge where the valve job ends and the bowl starts:

9037BADB-9B15-49FD-A647-BA9FD94480D8.png
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads