carb replacement suggestions

BTYM said

I don't disagree with you at all, but whether it's a squarebore or spreadbore carb, you absolutely can over carb your engine. The engine will use what it needs with that set up, but it may still be more than it needs. Just sayin. He's already bought it so it's null and void.

Click to expand...

Chrysler used 800 CFM Thermoquads on stone stock 8:1 318s from the factory and they worked fantastic. The reason is because a Thermoquad is a hybrid vacuum secondary carburetor. That means although the baseplate is mechanical in nature, the actual air door that allows air into the secondaries is totally vacuum operated. In other words, it only opens as far as the engine demands. So it would not matter if the carburetor was rated at 2000 CFM, as long as the primaries were not too rich, the carburetor would only flow what the engine demands. A stone stock 318 will not need 800 CFM until probably up around 7000 plus RPM. That means it will flow much less in a street car that only sees 5500 RPM as a red line. You really should read up more on carburetors and how they work before makin senseless statements. Rumblefish was dead on with his explanation to you. The fact that you don't buy it is not his fault, it's your stupidity.