455 4-bbl

Years 1970–76 Models 3

Also described as 455 4-bbl V8455 4-bbl (360 hp)

Documented applications

Firebird / Trans Am

1971–1976 Confirmed

Formula/Trans Am (455 HO ’71–72 was LS5); last 455 in 1976
1975–1976 Confirmed

"455 HO" badge ’75, plain 455 ’76; last big-inch Firebird

Grand Prix

1973–1976 Single-source

Corporate UPC (documented on Firebird); GP application plausible but not independently confirmed for GP

GTO

1970 Single-source

GTO; L75 = corporate 455 4-bbl UPC (documented on Firebird 1971–76); GTO-specific usage not independently confirmed
1971 Single-source

GTO option

This page aggregates every documented appearance of L75 in the Pontiac reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.