Who wants a mopar turbo kit?!?!

It’s not that carbs work on negative pressure, it’s that they work on pressure differential.

The atmospheric pressure around us is right around 14.7psi (depending on the weather). When the piston moves down on the intake stroke, it’s the pressure above the carb PUSHING the air in to fill the cylinder.

A lot of people visualize it as the piston is sucking the air in, but in reality it’s the positive pressure from the atmosphere pushing the air in.

There is a lower pressure in the intake plenum compared to above the carb. This pressure differential causes air to move through the carb. As the air moves through the carb, a venturi effect pulls fuel into the airstream.

With a turbo it’s no different, you just have added pressure in the carb hat above the regular atmospheric pressure that usually moves the air through the carb. The higher pressure still pushes air through the carb, still pulls fuel into the air stream, it just does it at a different airspeed then usual.

This airspeed difference (or more aptly put air mass difference) makes the air fuel curve/tuneup of a regular carb different then a blow through carb. That is the primary difference of why a regular carb doesn’t work well on a turbo motor as you turn the boost up further and further.

Make sense?