Why It Matters
The Pontiac W72 400 engine assembly covers the higher-output T/A 6.6 path offered in the 1977 Firebird Formula and Trans Am. It is tracked separately from the base L78 Pontiac 400 and the Oldsmobile-sourced L80 403, and should be verified with factory documents, engine codes, casting dates, cylinder-head evidence, and emissions equipment.
Also Known As
1977 Pontiac W72 400 engine1977 Trans Am T/A 6.6 enginePontiac W72 Performance Package engineT/A 6.6 engineW72 Pontiac 400 engine
