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APR HIGH PRESSURE FUEL PUMPS - S5 4.2L V8 (POST NOV 2008)

by APR
$2,798.95
SKU MS100077

PRODUCT DESCRIPTION 

The APR High Pressure Fuel Pump (HPFP) dramatically increases the maximum volume of fuel the HPFP can deliver. In doing so, the direct injection fueling system is capable of satisfying fueling requirements set forth by high horsepower setups. This is accomplished by increasing the displacement of the pump using high quality components to exacting tolerances. How the direct injection system works: A low pressure fuel pump (LPFP) in the fuel tank delivers fuel to the high pressure fuel pump (HPFP) at roughly 4 to 6 bar. Fuel pressure is then bumped up to a maximum of 136 bar, depending on factory parts, with the HPFP. Finally, high pressure fuel is delivered to the injectors, which spray directly into the cylinders. The problem: The volume of fuel the HPFP pump can displace is directly tied to the displacement of the pump (Internal bore size, and camshaft dictated stroke), and engine speed. The pump is driven off of a camshaft. Upgraded supercharger and turbocharger systems are capable of taxing this system, especially in the mid to lower RPM range where fuel volume is lower.

Features:

  • Dramatically increases the volume of fuel displaced by the HPFP
  • Maintains higher pressures under demanding situations
  • Fully rebuilt in house
  • Fully machine tested and broken in before shipping
  • New factory pumps included
  • Upgraded and weight matched spring
  • DLC coated piston
  • Heat-treated bearing-grade stainless steel material
  • Supports big power
  • .00004" dimensional tolerances
  • .00005" geometrical tolerances
  • Spring seals replaced
  • Brand: APR 
  • Part # MS100077