1974 Pontiac Firebird Trans Am 455 CID Super Duty
Manual Transmission Engine Specifications

Engine Code

W8

Engine RPO

LS2

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.3:1

Horsepower @ RPM

290@4000

Torque (Lb/Ft) @ RPM

395@3200

Head Casting

16

Carburetor

4-bbl

Carburetor

7044273

Intake Manifold

495107

Camshaft

Part #

Lift, I/E

.410 / .410

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

301 / 313

Overlap - Degrees

76

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifold - Right

490802

Exhaust Manifold - Left

490803

Distributor

1974 Pontiac Firebird Trans Am 455 CID Super Duty
Automatic Transmission Engine Specifications

Engine Code

Y8

Engine RPO

LS2

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.3:1

Horsepower @ RPM

290@4000

Torque (Lb/Ft) @ RPM

395@3200

Head Casting

16

Carburetor

4-bbl

Carburetor

7044270

Intake Manifold

495107

Camshaft

Part #

Lift, I/E

.410 / .410

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

301 / 313

Overlap - Degrees

76

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifold - Right

490802

Exhaust Manifold - Left

490803

Distributor