What is a Fuel Pressure Regulator? - A fuel pressure regulator is a device that maintains a constant pressure difference between fuel pressure and manifold air pressure. Fuel injectors are designed to spray fuel into the engine in a perfect spray pattern. When an engine is boosted, the rise in air pressure in the manifold can affect the injector's spray pattern - which can cause poor engine performance, or engine failure. A Fuel Pressure Regulator lets you set a base fuel pressure, then as boost pressure rises, the regulator increases the fuel pressure at a perfect 1:1 ratio, to ensure fuel is being delivered to your fuel injectors at the correct pressure. This is particularly important if performance injectors, or high-flow fuel pumps, have been installed.

Which Fuel Pressure Regulator is right for my application? - A fuel pressure regulator is sized according to how much fuel it is able to return to the fuel tank, while maintaining an optimum fuel pressure. When high flow fuel pumps are installed into a fuel system, the fuel pressure regulator must be able to match the flow of the new pumps. So, a Turbosmart FPR800 is rated to ''800HP'' not on its ability to support an 800HP engine, rather its ability to flow 800HP worth of fuel back to the tank when it's not needed by the fuel injectors. Therefore Turbosmart fuel pressure regulators are chosen to match the capacity of the fuel system. Other factors to consider when choosing a Turbosmart fuel pressure regulator include what kind of lines are being used (rubber push on or screw in -AN fittings), and whether or not your fuel rail is aftermarket (requiring the use of custom fuel lines).