Cliff's Quadrajet Parts and Rebuild Kits

General Category => Quadrajet Carb Talk and Tips => Topic started by: Marx3 on December 09, 2015, 01:11:22 AM

Title: Cfm ratings / opening distance
Post by: Marx3 on December 09, 2015, 01:11:22 AM

I have been wondering if any small cfm unit is capable of actually flowing 750 cfm, given a proper air flap opening distance?
Same goes for the large cfm units...
Will any large cfm unit actually flow those ~850 cfm, if the air flap and at what opening distance?
I know it is propably not as simple as that, but I suppose the opening distance of the air flaps will dictate the number of cfm the carb can flow at a maximum.

Title: Re: Cfm ratings / opening distance
Post by: Frank400 on December 11, 2015, 08:08:52 PM

http://cliffshighperformance.dreamhosters.com/simplemachinesforum/index.php?topic=2248.msg10510#msg10510

Title: Re: Cfm ratings / opening distance
Post by: qjetsrule on December 15, 2015, 05:57:46 PM

I think the cfm can be calculated by a dyno or flow bench, but a lot depends on the motor. A strong motor will actually pull more cfm than a carbs rating and vice versa. As Cliff points out there are extremely fast cars in stock and superstock that must run the 750 cfm rated quadrajet. I'm sure the dyno shows more than 750 cfm going through those motors.