Matt - both Stromberg and Zenith offered aftermarket carbs that would work exceptionally well, also Zenith offered a type 228 for the G.M.C. 270 that works exceptionally well.

Tim: here are two links on CFM/carburetor selection:

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

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

Your method of picking one from an engine of similar displacement also works MOST of the time. It does NOT work if the engines are extremely dissimilar. Engines with vastly different maximum RPM, engines with different configuration (oversquare/undersquare), and generally sufficiently dissimilar to muddy the waters. Thus a carburetor designed for a 350 Pontiac (high torque, low RPM) doesn't generally work well for a 350 Chevy (low torque, high RPM).

As far as CFM is concerned (read the article), one of the most knowledgeable comments came from Mark Twain "Figures don't lie, but liars figure!". wink

Jerry - take a look at the last paragraph on the first link wink

Jon.

Last edited by carbking; 01/05/2018 5:26 PM.
Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop