Valve notches are legal in SS....... but they probably weren’t always.

In Stock, at one point it was pretty common to hammer some reliefs into stock pistons with some junk heads and valves.

Then, NHRA made a rule against it.
No valve contact witness marks allowed on the pistons.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads