Audi VW Direct Injection High Pressure Fuel Pump - APR MS100144

The APR High Pressure Fuel Pump (HPFP) increases maximum volume of fuel the HPFP can deliver by 37% over stock! 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 200 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 lobe on the camshaft. Larger turbocharger systems, and ethanol usage are capable of taxing this system, especially in the mid to lower RPM range where fuel volume is lower.

The APR solution:

We dramatically increase the volume of fuel the HPFP can displace at every RPM by increasing the displacement of the HPFP. This is accomplished by increasing the bore diameter of the pump's internal pressurizing cylinder. It's important to understand, despite the name, an HPFP upgrade is not necessary designed to increase the engine's fuel rail pressure. The primary goal is to increase the volume of fuel available, which will keep fuel pressure steady even in the most demanding of situations!

High-quality components and extreme tolerances:

The HPFP internals must be machined to extreme tolerances and installed in a clean environment or the pump can easily fail. Dimensional tolerances on the APR HPFP are as tight as .00004" and geometric tolerances are as tight as .00005". The plunger and barrel are created from certified and heat-treated bearing-grade stainless steel and the plunger undergoes a special diamond-like coating process for exceptional surface hardness and ultra-reliable operation. To prevent float associated with altering the plunger's mass, APR supplies each unit with a properly specified spring. All necessary internal seals are replaced.

Internal testing:

All APR HPFPs are assembled in-house under strict assembly guidelines. Each pump is then tested on our test rig to ensure the pumps operates as designed. This step is important for several reasons. It's critical to determine if a pump has a failure from an incorrect install, a leaking seal, or a bad solenoid. Secondly, a seized pump on the vehicle at startup can cause damage to the engine's camshaft. By testing each pump, we all but eliminate this possibility.

Proven track record:

APR pioneered HPFP upgrades in the early days of VAG direct injection engines. Soon after, APR became an OEM supplier of HPFP and GDI components to VAG for use in various race cars, racing series, project cars, and concept vehicles. The APR HPFP has been at the center of countless motorsport victories across the globe and has operated with a nearly perfect track record since the program's motorsport-backed inception in 2006. With tens of thousands of pumps sold, APR has a wealth of knowledge, and manufacturing expertise necessary to deliver a product that will and has stood the test of time.

OEM Components:

Critical to the design of the APR HPFP is the use of only genuine Hitachi components, made in Germany, which consists of sensors, pump bodies, and other critical components that must operate with OEM levels of reliability. All APR components are made in the USA using medical-grade precision machinery that goes well beyond the tolerances capabilities found at automotive engineering companies.

Features:

• Dramatically increases the volume of fuel displaced by the HPFP by 37%
• Maintains higher pressures under demanding situations
• Fully rebuilt in house
• Fully machine tested and broken in before shipping
• Includes a new OEM pump
• Upgraded and weight-matched spring
• Titanium retainer
• DLC-coated piston
• Heat-treated bearing-grade stainless steel material
• .00004" dimensional tolerances
• .00005" geometrical tolerances

Emissions:

This part is legal under the provisions of EPA’s Tampering Policy dated November 23rd, 2020. The company has a reasonable basis (test results) to verify that this product allows the vehicle to operate within legal emissions standards and is therefore legal to be sold for on-street use in all states that accept the legal provisions of the Clean Air Act and the EPA Tampering Policy. This product is NOT LEGAL FOR SALE OR USE IN THE STATE OF CALIFORNIA. Testing with the California Air Resources Board, in order to achieve 50-state compliance, is pending with CARB. Once testing is complete with California, and an E.O. number is issued, this product will be updated to 50-state legal status.

Tech Resources:

Install Instructions