Factory Q-Jet CFM Rating?
 

What was the cfm rating on the factory Rochester carburetor that was used on a 402BB?
Thanks,
Dewayne 70cst

I'm pretty sure it's a 750CFM. I think all 4bbl V8s got the same Quadrajet, right? Mine's only a 350...

The Edelbrock #1901, which is a clone of the original carb I had on there, is definitely 750CFM, and the two look too close to be far off in CFM.

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Project 1970 - soon to be seen at http://milhouse.treylis.org:81/

There was a 750 cfm,& a 795 cfm Q jet.....I cant say for sure,but the big Buicks & Olds used the 795 cmf carb........69 longhorn.

bb and sb q-jets are different, sb are 600 cfm and the bb are 750 i think....

Thanks Guys...
My carb is beyong repair so I'm going to replace it so I wanted to be sure I had a similiar rated carb. I'm not sure which carb I'm going with but looking at Holley Avenger 770cfm or the Edelbrock.
Dewayne 70cst http://67-72chevytrucks.com/board/ubbhtml/smile.gif

You are right, as usual, Longhorn. 750 & 795 or 800, but who's counting. When you look down inside the big one (maybe 455 Buick) the venturies are physically bigger.

The QJets referred to a 750 and 795 cfm are the same carb. There is an 800 or 850 cfm version (can't remember which), but it was never used on any truck motors. They were mostly used on the larger displacement Pontiac and Cadillac engines.

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Tim