pamsman

[pamsman]

New here and need expertise...I have a 401 in my 66 Riv. When I bought it, it had an Edelbrock carb (new) on it, still does...i would like to know what the correct CFM should be for a 401 intake,,,550? 600? 750? 800-850? People tend to over carb their motors and I believe that is the situation here....I would also appreciate if anyone knows of a link that can show cfm specs for the 401..Thanks guys! call me at 270-779-1641 if you want to talk....anytime...I am also the regional Coordinator for ROA in my state...Andy

[DocModisett]

Andy,,,, I have run the stock afb which is about 550 cfm, I have run the holly 600 cfm... 670cfm ,, 950 cfm 3 barrel, 1050 3 barrel..... my nailheads did not have any trouble handeling any of them.... the factory dual quad set up flows about 1200 cfm total...
the most common mistake that I see guys do is putting a big carb on without installing a hot cam to handle it .... that and using carbs with ''straight'' linkage to the secondaries.... the rpms need to come up before the secondaries come in....and I see guys installing bigger carbs and then doing nothing about opening up the air cleaner assembly to handle it... and then there is the exhaust system that needs to be opened up to take the increased amount... got to look at the total pkg.....the only thing that I have had to tend to is the holley carbs tend to idle on the rich side... and I usually drill the idle air bleeds out bigger to change the ratio to leaner....

[Bob]

This is probably what you are looking for:

http://www.teambuick.com/reference/carb_tidbits.php

http://www.teambuick.com/forums/view...cfm_calculator

If you are not modifying the motor, I would find a stock carb.