A 235 engine at 3,000 RPM only flows 204 CFM, and that's if it is getting 100% volumetric efficiency. At 90%, which is a much more realistic figure, it's flowing 184 CFM. What is it supposed to do with more than twice that CFM capacity, when a 500CFM carburetor is installed?
A small block 350 at 5,000 RPM flows 506 CFM at 100% efficiency. At 90%, it's only 456, so the 500 CFM 2-barrel is plenty for normal street use on a 350!
All that putting a too-big carburetor (or two of them) on a stovebolt accomplishes is that it creates a terribly throttle-sensitive situation that causes stumbles, flat spots, and backfires. Driving an over-carbureted engine is a major pain in the butt, one I can definitely do without!
Jerry
