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Alex V. · 03-22-2018, 02:03 PM

The Quadrajet was only made in 2 CFM's: 750 and 800. The vacuum secondaries make it, in a way, a variable CFM carb. because when adjusted properly the secondaries only open as far as engine vacuum will pull them open. Many factory small blocks came with Q-jets - 650 is a good minimum for a stock big block but when speaking of a Q-jet it won't be "too much".

03-22-2018, 02:03 PM	#13
Alex V. Registered User Join Date: Mar 2013 Location: Campbellsville, KY Posts: 888	Re: cfm quadrajet? The Quadrajet was only made in 2 CFM's: 750 and 800. The vacuum secondaries make it, in a way, a variable CFM carb. because when adjusted properly the secondaries only open as far as engine vacuum will pull them open. Many factory small blocks came with Q-jets - 650 is a good minimum for a stock big block but when speaking of a Q-jet it won't be "too much". __________________ Alex V. ------ 1967 C10 Suburban, 350/NP435, Green/Green, PS, PB, HD cooling, charging, shocks, and springs. 1985 GMC C3500 SRW, Sierra Classic, 454/TH400, white/blue.