Yep, a picture is worth a 1000 words...........

What you have is a small block Chevy, non Vortec, prior to 1987 (I think 87 is the start of Vortec. The carb is a Rochester Quadrajet.

No, the 750 is way too big for a 350 Chevy (assuming this engine is a 350 and not a 305) You want no more than a 600 CFM or you will be overcarbed.

Evidently your intake is set up for spreadbore and squarebore (from what others have said, but to be sure pull the carb and look at the base pattern).


Don