2.063" head. Early '61. Except HP.
5.7L / 348 OHV V8 16V Chev. 4.125" Bore 58-61
GM
6.7L / 409 OHV V8 16V Chev. 4.312" Bore 61-65
GM
GM348C-CH | 5.7L / 348 OHV V8 16V Chev. 4.125" Bore 58-61
CHEVROLET
GM409C-CH | 6.7L / 409 OHV V8 16V Chev. 4.312" Bore 61-65
CHEVROLET