I'm swapping to a four barrel, the intake im getting is from a 73 buick skylark and the engine i have is a 71 350 in a skylark. What are size carb should I put on?

My opinion: a 600 CFM carb should be plenty for a stock motor.

If you put a cam, headers, and more on, then you might need a 650. But for now a 600 CFM will do fine.

I think a spreadbore carb (quadrajet) will give you best "all around" performance because of the smaller primary venturis.

-Bob Cunningham

If you get the complete system( carb and intake) use the Q-jet that is there. I firmly believe that for street use, you cant beat a Q-jet. The 350 Q-jet has some different jetting than the 455 Q-jet, but my son runs a 455 carb on his 350 ,and it runs very well.