Walbro 400 & 450 LPH (E85) In-Tank Fuel Pump & ScienceofSpeed Installation Kit


 The Walbro 400 liter per hour (LPH) fuel pump is the ultimate solution for the high power NSX. The pump flows 400 LPH of gasoline at a base pressure of 43.5 PSI at 13.5 volts (an increase of approximately 158% over the factory pump). The 450 liter per hour (LPH) E85 compliant fuel pump is compatible with either gasoline or E85 and offers a slight flow increase.

Utilizing a proprietary turbine mechanism with an enlarged base, the Walbro 400 LPH pump offers high flow and reliable quiet operation.

The Walbro 400 / 450 LPH fuel pump is a universal design and most vendors do not sell the required parts to install in to NSX. ScienceofSpeed includes with the fuel pump a complete NSX-specific installation kit allowing direct replacement of the factory fuel pump and step by step installation instructions from ScienceofSpeed.

This fuel pump for example can supply 350 LPH (or 972 cc/min per injector in the NSX engine) which is enough flow for approximately 870 BHP (gasoline) or 670 BHP (E85) based on fuel rail pressure at 60 PSI, fuel pump voltage at 13.5V, and BSFC at .60 (gasoline) or .78 (E85), and injectors at 80% duty cycle. This example is approximate, and should be verified based on the application's specific conditions. See fuel pump comparison graph.

Important note: For applications requiring more than 10 amps of current (see current requirements of this fuel pump below), the factory fuel pump wiring circuit must be upgraded. ScienceofSpeed offers a complete fuel pump power distribution kit shown below.

2000-05: requires factory 1991-99 NSX fuel pump carrier.

Walbro 400 LPH Fuel Pump (gasoline only) & ScienceofSpeed Installation Kit - NSX, 1991-99


Walbro 450 LPH Fuel Pump (gasoline or E85) & ScienceofSpeed Installation Kit - NSX, 1991-99