This Pump works off oscillations generated by the engine. Oscillating pumps will also work on inverted or side-mounted engines. This pump can be used with ALCOHOL BASED FUELS ONLY This is the version called the "silver hex screw". Each time the engine fires, the pump reacts with a short rotation...

The VP-40 regulating pump is capable of performing like no other fuel delivery system. It delivers an ideal .25 PSI to any model carburetor from a .15 to a 3.0 cu.in. engine. The pressure remains constant throughout the entire speed range, making the carburetor adjustment easy and simple. Once the n...