Curt - there is a partial chart of CFM for various Rochester carburetors in the Doug Roe book; you need to know the internal venturi size (measure it) and then compare it to the chart in the book.

Remember that 2-barrels and 4-barrels are rated differently. See the article on our website for ratings conversions. Here is the link:

http://www.thecarburetorshop.com/Carbshop_carbsizesandCFM.htm

More information would be necessary before I could suggest if it were too much. In the "for what its worth" category, I have successfully run a 400 CFM Carter 4-barrel on a 195 CID Pontiac four, a 132 CID Toyota 4, and a 120 CID Ford 4. I also had a pair of 500 CFM 2-barrels on a 120 CID Datsun 4 which was factory carburetion for the engine! Much depends on the state of tune of the engine, the manifold and head design, AND how you plan to use the vehicle.

Jon.


Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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