The Q-jet that came on the 350 from the factory was capable of flowing up to 750 CFM. Like Madman stated, the Q-jet will only deliver what the engine demands. 750 is not too big for the 350. The link I posted is the carburetor I would use if I didn't have the good Q-jets I have. Look at my signature. That 470 demands a lot of air. I think the SA 870 would make a good street carburetor for my engine.