Choosing a carb that is too large will create an engine that operates too rich.
A properly sized carb will provide better drivability by creating better idle, fuel economy and throttle response.
The goal is to create an engine where all the components are matched and sized to compliment each other. Taking the time to assure this match will result in improved driving performance and driving pleasure.
Selecting the correct carb is a function of three variables. By correctly answering these questions, you can select a carburetor tha will meet your performance needs without creating drivability problems.
1. Engine cubic inches
2. Maximum RPM. You must be very realistic here. Most stock and mild aftermarket cams are designed to max out at 5000 RPM.
3. Engine efficiency. In general terms this measures how well your engine moves the air/fuel mixture throughthe engine. This number is affected by many engine components including the carb, manifold, cylinder head, camshaft and valvetrain components, piston and combustion chamber design, and exhaust system.
Next week I'll post the entire checklist that you'll need to fill out in order to purchase the proper size carburetor. Or you can call me and I'll fill it out and order it for you.
Do it Right, Do It Fast at Bobby C. Speed Connection