Originally Posted by oldbogie
Probably yes, the static compression ratio even with 64 cc chambers, with the original pistons, a .025 inch stock deck clearance, and a .020 thick gasket only generates 8.4 to 1. For a Vortec style chamber in cast iron this will easily operate on regular unleaded especially with the stiff gearing you've got.
You're far away from compression requiring premium unleaded with this engine and its original cam. To get into compression ratios requiring premium fuel you'd need to change to a flat top piston along with small chambered head.
Thanks for the info, that puts me at ease no matter what route I take.