looking for some "how to" here..... Adding 2 vintage McCulloch superchargers to an engine with 2 carbs. How do I "pressurize" a carb? Help? TIA, James
So you're blowing through the carbs with the supercharger, correct? If so, you can do it two ways: 1) Put a bonnet on the carburetor, drill holes in the base on each side that meet the throttle shaft bore. Install some brass tube in the holes you've drilled and connect a line from the bonnet to each tube. This will feed pressurized air to each side of the throttle shaft, creating an "air seal" whic will keep mixture from blowing out. 2) Put the whole carb setup inside a sealed box and pressurize the box (Studebaker did it this way). You'll need to make sure you have solid plastic or hollow brass floats in the carb, if you have hollow plastic floats they will collapse. The throttle cable going into the box makes a minimal air leak that won't bother anything. Good luck Shawn
I only have experience with the foam filled plastic floats but I have been told that the brass ones will hold up to boost pressure ok. Shawn
What are you putting together? Whatever it is, it sounds rad... My 63 Studebaker Avanti has a special carb that the ductwork hooks up to, and it blows right through the carb, no sort of pressure box around it..... I think it's special for the application But putting the whole carb in a pressurized box would work well. Make them out of plexiglass so you can still see the carbs!
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