Find some stock '86 to '91 318 roller engine pistons, they are 9.2:1 cr stock from the factory.
Mr. Gasket. 028 ths head gaskets will help up cr too. Not only thinner, but they fill the hole better than the Felpro universal 318/360 head gasket.
Pistons, head gaskets, 340 cam and away you go. Of course a 4 bbl is what wakes it up. 1406 Edelbrock, good match for the 318s.
View attachment 1716338932
9.2:1 cr pistons stock 318, .040 ths in the hole.
☆☆☆☆☆