One of the most scarce carburetors today is the sought-after 1967 Pontiac Quadrajet. General Motors released a few part numbers depending on the engine size, emissions, and model.
The Pontiac 400 and the 428 engine with an automatic transmission (A/T) utilized the 7027262, while the standard transmission (S/T) used the 7027263. However, that is federal emissions or non-smog-equipped models.
In the 1960s, the Environmental Protection Agency (EPA) was pushing General Motors, Ford, and Chrysler [The Big Three] to abide by the smog regulations in California. The Big Three’s plan of attack was to incorporate factory-modified carburetors for smog-equipped cars. General Motors, or in this case, Pontiac, used 7037262 and 7037263 for smog-equipped cars sold in California. The same rule applies to A/T and S/T vehicles. In other words, 7037262 is for A/T, while 7037263 is for S/T cars.
Earlier, I mentioned that models played a factor. Pontiac introduced the Firebird in 1967 with a 400 engine. The Firebird with an A/T used 7027272, and the S/T took 7027273. The same applies to Firebirds sold in California. A/T used 7037272, and S/T utilized 7037273.
Some may ask, what about the Ram Air (RA) option? In 1967, Pontiac offered an optional 400 engine used on Firebirds and GTO’s with an RA option. 1967 A/T vehicles with an RA option used 7027276, while the California model used 7037276. Models with an S/T used 7027271 for federal and 7037271 for California.
In the later years, General Motors and independent rebuilders interchanged both carburetors for the Firebird and non-Firebird; however, purists debate otherwise. In other words, if you have a 1967 Pontiac Firebird sold in California with an S/T, you must have 7037273.
In conclusion, the 1967 Pontiac Quadrajet is scarce. Engine sizes, emissions, and models play a factor. Later on, General Motors and independent rebuilders interchanged carburetors. Purists fought against this notion and required Pontiac owners to install the correct carburetors on their vehicles.