Exergy Performance

Exergy Performance

Exergy Performance is a diesel fuel system specialist focused on high-output injection components for Cummins, Duramax, and Power Stroke diesel platforms, producing fuel injection pumps, injectors, injection lines, lift pumps, and supporting fuel system hardware that addresses the OEM injection system's limitations at elevated power levels. Diesel truck owners who push beyond the factory tune with larger turbochargers, performance camshafts, and aggressive fueling strategies quickly reach the capacity ceiling of the stock injection system, and Exergy provides the fuel system architecture that allows the engine to support those power levels safely and consistently. The Duramax LML CP3 conversion kit, which replaces the problematic CP4.2 high-pressure pump with the more robust CP3 design proven in earlier Duramax generations, is one of Exergy's most important product solutions for preventing the catastrophic fuel system contamination failure that affects stock LML and L5P trucks running modified fueling strategies. Serious diesel performance builders choose Exergy when the stock fuel system becomes the bottleneck preventing the build from reaching its target power level reliably.

Popular Upgrades

Exergy's most popular products include the New Generation reman and upgraded CP3 injection pump for LBZ, LMM, and converted LML Duramax platforms that provides increased flow capacity over the factory CP3, high-flow injectors for 5.9L and 6.7L Cummins in 30 to 100 percent over-stock tip configurations matched to specific horsepower targets, Duramax LML and L5P CP3 conversion kits with all necessary hardware for a clean installation, and Exergy upgraded high-pressure injection line sets that flow more fuel than OEM lines and support the higher pressure delivered by upgraded CP3 pumps. Lift pump systems from FASS and AirDog, which are sold alongside Exergy injection components as supporting hardware, are the first recommended fuel system upgrade before any CP3 or injector work to ensure the high-pressure pump receives clean, adequately pressurized diesel fuel at all engine speeds.

Performance and Handling

An Exergy upgraded CP3 pump on a modified Duramax provides 20 to 40 percent more fuel volume than a stock pump at equivalent rail pressure, which directly expands the horsepower ceiling the injection system can support before fuel pressure drops under full load at high rpm. Exergy injectors sized for the specific horsepower target ensure that the increased fuel supply from the CP3 upgrade is actually delivered into the cylinder at the correct spray pattern and quantity rather than being limited by injector flow capacity. Pairing Exergy fuel system components with a FASS or AirDog lift pump eliminates the aeration and fuel supply pressure drop that can damage high-pressure pumps, protecting a significant investment in injection hardware.

What is the CP4.2 failure issue on the Duramax LML?

The CP4.2 high-pressure injection pump used in 2011 to 2016 Duramax LML and 2017 to 2019 L5P trucks is known for catastrophic internal failure that contaminates the entire fuel system with metal debris when the pump's internal piston and cam lobe experience accelerated wear, which is most common on trucks running aggressive tune files or biodiesel blends that reduce lubricity below the pump's design requirement. When the CP4.2 fails, the debris travels downstream through the injection lines and into all six injectors, typically requiring replacement of the pump, all injectors, injection lines, fuel filter housing, and fuel rails at a repair cost of $8,000 to $15,000 depending on parts and labor rates. The Exergy CP3 conversion kit replaces the CP4.2 with a proven CP3 design, eliminating the failure mode entirely for modified or heavily used trucks.

Do I need a lift pump with an Exergy CP3 upgrade?

Yes, a lift pump from FASS, AirDog, or FlowMax is strongly recommended with any Exergy CP3 pump upgrade because the CP3's internal transfer pump is less efficient than a dedicated lift pump at pulling fuel from the tank under high demand conditions, particularly on trucks with partially empty tanks or long fuel line runs on lifted applications. A FASS 150 or AirDog II-4G system provides 150 or more gallons per hour of filtered, separated diesel fuel to the CP3 at stable pressure, ensuring the high-pressure pump receives the supply it needs to maintain consistent rail pressure. Installing a lift pump alongside the CP3 upgrade also provides a last line of defense against water contamination that can cause injector seat damage on high-flow injection systems.

Why These Parts Fit Right

Exergy fuel system components are listed by engine family, model year, and horsepower target to confirm correct pump specifications, injector sizing, and hardware compatibility before ordering. CP3 conversion kit product pages include all required hardware and installation notes for LML and L5P applications. Fast shipping and expert diesel support are available for any Exergy fuel system fitment or installation question.

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