1975 Pontiac Firebird Trans Am 400 CID
Manual Transmission Engine Specifications

Engine Code	WT
Engine RPO	L78
Displacement	400 CID
Bore x Stroke	4.1212" x 3.750"
Compression Ratio	7.6:1
Horsepower @ RPM	185@3600
Torque (Lb/Ft) @ RPM	310@1600
Head Casting	5C
Carburetor	4-bbl
Carburetor - Federal	7045263
Intake Manifold	495106
Camshaft
Part #
Lift, I/E	.377 / .415
Rocker Arm Ratio	1.5:1
Duration I/E - Degrees	269 / 282
Overlap - Degrees	59
Intake Valve Dia -	2.11"
Exhaust Valve - Dia	1.66"
Distributor

1975 Pontiac Firebird Trans Am 400 CID
Automatic Transmission Engine Specifications

Engine Code	YS
Engine RPO	L78
Displacement	400 CID
Bore x Stroke	4.1212" x 3.750"
Compression Ratio	7.6:1
Horsepower @ RPM	185@3600
Torque (Lb/Ft) @ RPM	310@1600
Head Casting	5C
Carburetor	4-bbl
Carburetor - Federal	7045274
Carburetor - California	7045564
Intake Manifold	495106
Camshaft
Part #
Lift, I/E	.377 / .415
Rocker Arm Ratio	1.5:1
Duration I/E - Degrees	273 / 289
Overlap - Degrees	54
Intake Valve Dia -	2.11"
Exhaust Valve - Dia	1.66"
Distributor