primary/Secondary CFM-rating?

[Marx3]

I was wondering... what is the Cfm rating om the primary side only vs on the secondary side only? for both 750 and 800 Cfm carbs... Has this ever been meazured?

[Schurkey]

I was wondering... what is the Cfm rating om the primary side only vs on the secondary side only? for both 750 and 800 Cfm carbs... Has this ever been meazured?

So far as I'm aware, the secondary side of the two carbs is the same.  Set 'em up equivalently--same opening angle of the throttle plate and same opening angle of the air valve--and they flow the same.

So the question is how much do the primaries flow; and the obvious answer is that the "big" primaries flow 50 CFM more than the "little" primaries.

By the way, all of the DualJets I looked at seemed to use the "800-style" venturi arrangement.  So another way to frame this question is "how much does a DualJet flow when rated as a 4-barrel carb?"

[Marx3]

heh, point taken, but what does a dualjet flow at 3" hg then?

[Rocky Rotella]

This might help answer your questions.  It's from the Dec 2006 issue of HPP. 

http://www.highperformancepontiac.com/tech/hppp_0612_rochester_quadrajet_carburetor/index.html

[Schurkey]

Blast from the past.

Found an airflow chart in a recent thread on another forum.
http://www.v8buick.com/showthread.php?296829-Checking-on-CFM-size-for-a-1974-455-2bbl

 I'm shamelessly re-posting the chart here.

[Ethan1]

Blast from the past.

Found an airflow chart in a recent thread on another forum.
http://www.v8buick.com/showthread.php?296829-Checking-on-CFM-size-for-a-1974-455-2bbl

 I'm shamelessly re-posting the chart here.

 Interesting! Thank you for posting this.