Authenticity reference

Cylinder head family

trim correctness · reported

A photographed 1977 Trans Am showing Goldenrod Yellow paint, black and red graphics, Trans Am scripts, T/A 6.6 shaker callout, body-color mirrors, and Snowflake wheels; W72 identity, finish, equipment, restoration, and condition remain specific to this car. 1977 Pontiac Firebird Trans Am W72 400

Reference Details

Common issue: Base 6.6 Litre 6X-8 heads presented as W72-correct.
Confidence: reported
Correct value: 6X-4 small-chamber heads reported for T/A 6.6/W72
Where to check: Cylinder head casting/secondary stamping area during engine inspection

Cars With This Authenticity Marker

1 linked car page.

1977 Pontiac

1977 Pontiac Firebird Trans Am W72 400

Factory Pontiac Firebird Trans Am configuration

Sources & Documentation

78TA.com / Hitman's Pontiac Trans Am Site W72 Pontiac 400