carb cfm

[Michael Anderson]

looking in to replace carb .What is the correct cfm for the 429?

[Michael Anderson]

thanks for the info

[Jason Edge]

CFM ratings were not listed in the Shop Manuals or Dealer Data Books and Carter was really vague in terms of the Carter AFB which could range from 400 cfm up to 900 cfm from what I have read. 

Rochester 4GC is a bit easier as they only made 3 CFM's during this time period: a 486, 553, and 692 cfm carb. You can compare the venturi and main bore diameters (1 1/8 1 15/32 / 1 7/16 1 11/16) to quickly lock in on the fact it was a 553 CFM carb. Since the specs for 63 and 64 are the same you pretty much assume the carbs are the same CFM rating.

As far as the Carter AFB, I had done some research that let me to believe their carb was a 575cfm. There were tons of model # but looking at later ones with CFM rating seemed to narrow it down to 500 CFM to 575 CFM, with the 575 CFM being the closer rating.