Rochester 4 bbl on big 66 Pontiacs?
 

Did some big 1966 Pontiacs with 4 barrel carburetors come standard with Rochester units instead of Carter AFB's? I have seen a large number of big 1966 Pontiacs with Rochester4 barrel carburetors but there is no mention of Rochester 4 barrels for these cars in the 1966 Pontiac Chassis Manual. Maybe there were all replacement units?

I assume you are talking about the spread bore Rochester Quadra-jet.? To my knowledge, they were not factory equipped on any Pontiac engines in 1966 with the exception of the OHC-6 Sprint engine. Thus why tri-power was still the top induction system in 1966. The Quadra-jet replaced the tri-power option in 67 on all Pontiac performance engines, providing about equivalent induction with much less cost, complexity, and potential fuel leaks. Although the cool factor was greatly diminished. The somewhat undersize AFB was often changed along with the intake a small performance upgrade in those 66 engines. Of course a Q-jet will not be a direct bolt-on to a 66 intake manifold without some type of adapter. Also the air cleaner will not be a direct replacement with the AFB's of that time period.