1978 Pontiac Firebird Trans Am 400 CID T/A 6.6
Manual Transmission Engine Specifications

Engine Code

WC

Engine RPO

L78 w/W72

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

8.1:1

Horsepower @ RPM

220@4000

Torque (Lb/Ft) @ RPM

320@2800

Head Casting

6X

Carburetor

4-bbl

Carburetor - Federal

17058263

Camshaft

Part #

10003402

Lift, I/E

/

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

NA / NA

Overlap - Degrees

NA

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

1103315

1978 Pontiac Firebird Trans Am 400 CID T/A 6.6
Automatic Transmission Engine Specifications

Engine Code

X7

Engine RPO

L78 w/W72

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

8.0:1

Horsepower @ RPM

200@4000

Torque (Lb/Ft) @ RPM

320@2800

Head Casting

4X

Carburetor

4-bbl

Carburetor - Federal

17058266

Camshaft

Part #

10003402

Lift, I/E

NA / NA

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

NA / NA

Overlap - Degrees

NA

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

1103315