The Radium Engineering DFPR (Dual Fuel Pressure Regulator) was designed specifically for custom fuel systems that use both direct injection and port injection. The DFPR permits independent fuel pressures for each system while using 1 fuel feed input. Furthermore, the architecture suppresses the aggressive pressure spikes created by the mechanical (positive displacement plunger-type) HPFP pump used for direct injection. FPR1 is used for direction injection and FPR2 is used for port injection.