I have 2 Quadra-jets, one has the round medal tag showing it came on a 1966 Oldsmobile with an automatic trans. The second one which has same 66/67 divorce choke, the lever on top of the driver side 4 barrel air flap, and part numbers on different parts that match the first. BUT doesn't have a round medal tag, nor a place for it, also no vertical numbers on main carb body. Body has nice original color, no signs of milling off of raised circle where tag would be, just clue residue from a sticker of some sort.



I could not find an explanation for this. I discovered that Chevy was the only one to use the Quadra-jet in 1965 supposedly with same round medal tag. So any idea how an unmarked or I.D. numbered carb would have escaped Rochester, New York? Only difference I can find is one has threaded PCV vacuum tube and number on bottom of fuel inlet one is 1 and other is 2.

 

Original 1966-67 Oldsmobile Q-jets have the round metal tag with the carb number. The other one is a service replacement with the carb number stamped in the customary place on the side of the carb by the secondary throttle arm.