TECH BULLETIN

Vapor lock is when part of the fuel system reaches a temperature above the boiling point of the fuel. Vapor Lock usually occurs at idle, stop and go driving, or after the engine is shut down.

The primary cause of vapor lock is high under hood temperature. Occasionally cars will have the fuel lines routed too close to the exhaust or other heat producing elements, but most of the time the under hood temperature is just to hot.

The Race Pump is insulated from the engine by a heatshield/gasket that installs between the pump and the engine block. With the heatshield/gasket in place, the Race Pump will run at the same temperature or less than a conventional fuel pump.

Some of the big block Corvettes that were known for high under hood temperatures had a bleed line that allowed a small amount of fuel to flow back to the tank constantly. This flow was enough to keep the fuel pump and lines cool enough to prevent vapor lock. The Race Pumps idle bleed regulators can be used in this manner.