Injection Pumps & Controllers for Cummins CP3 and Duramax LB7

What This Collection Covers

This collection centers on high pressure common rail injection pumps and their supporting control and conversion hardware. A correctly sized pump supports the fuel volume needed for stock restoration, towing, or high horsepower diesel builds.

CP3 and CP4.2 Pumps

The CP3 and CP4.2 are different high pressure pump designs. Select the exact pump listed for your engine or use a complete conversion kit engineered for the application.

Cummins Pump Options

Cummins applications include 5.9L and 6.7L platforms with stock replacement, Sportsman, stroker, Alpha, and dual pump options. Confirm early or late 6.7L configuration because pump and line details vary by year.

Dual Pump Controllers

Dual pump systems require a compatible controller, harness, plumbing, and calibration plan. Match the controller to both pump arrangement and truck generation.

Duramax Pump Options

Duramax applications include LB7, LLY, LBZ, LMM, LML, and newer platforms. CP3 conversion parts can replace the factory system on supported applications, but every kit needs the correct pump, line, brackets, fittings, and tuning.

High Pressure Lines

High pressure lines and fittings must match the pump, rail, injector arrangement, and intended pressure. Never reuse damaged lines or contaminated fuel components.

Fuel System Planning

A high output injection pump is one part of a complete diesel fuel system. Injectors, lift pump capacity, filters, rail pressure control, return flow, tuning, and fuel cleanliness all need to support the final goal.

Professional Installation

Injection pumps and high pressure lines require strict cleanliness and correct torque procedures. Professional installation is recommended for pump swaps, conversions, and high horsepower fuel systems.

Top Brands

• Exergy. CP3 and CP4.2 pumps for Cummins and Duramax builds
• Fleece Performance. Dual pump control, CP3 conversion, and fuel system hardware
• BD Diesel. Stock replacement and performance diesel pump products
• Industrial Injection. High performance Cummins and Duramax fuel system parts
• AirDog. Lift pump and fuel filtration systems
• Sinister Diesel. Diesel fuel, intake, and cooling components
• Wehrli Custom Fabrication. Duramax CP3 conversion lines and hardware

How to Choose the Correct Part

• Confirm the exact year, truck model, engine, and emissions configuration
• Identify the engine family such as Cummins, Duramax, or Powerstroke
• Verify the original pump type and any prior conversion hardware
• Match the pump output to injector size and planned horsepower
• Confirm required lines, fittings, brackets, sensors, and harnesses
• Plan compatible tuning before changing pump capacity
• Inspect the lift pump, filters, and fuel supply for restrictions
• Keep all high pressure fuel components exceptionally clean
• Replace seals, gaskets, and single use hardware as the maker directs
• Use a qualified diesel technician for pump timing and high pressure installation

Common Questions

What is a CP3 injection pump?

A CP3 is a high pressure fuel pump used on many common rail diesel engines. It supplies pressurized fuel to the rail and injectors.

What is a CP4.2 pump?

A CP4.2 is another high pressure common rail pump design. It has different fitment, plumbing, and service needs from a CP3.

Can I replace a CP4.2 with a CP3?

Some engines have complete conversion kits. The swap needs the correct pump, brackets, high pressure lines, fittings, hardware, and tuning for the specific vehicle.

What is a dual CP3 system?

It uses two compatible high pressure pumps to supply more fuel volume for a large injector or high horsepower diesel build.

Do I need tuning after an injection pump upgrade?

Yes in most performance applications. Pump capacity and rail pressure strategy must match the injectors and engine calibration.

How do I choose a Cummins CP3 pump?

Match the truck year, engine generation, pump arrangement, injector demand, and power target. Confirm early or late generation details before ordering.

Are Duramax CP3 conversion parts model specific?

Yes. LB7, LLY, LBZ, LMM, and LML applications can use different parts. Choose a kit listed for your exact Duramax engine and model year.

Should I replace high pressure lines during a pump job?

Replace any damaged or contaminated line and follow the kit instructions. High pressure components must seal correctly and remain very clean.

What supports a larger injection pump?

Adequate lift pump flow, clean filtration, compatible injectors, fuel rail control, tuning, and a healthy engine are all important.

Can Black Ops Auto Works help with pump fitment?

Yes. Provide the truck year, make, model, engine, current pump, and build goal for fitment help.

Why Buy from Black Ops Auto Works

Black Ops Auto Works stocks parts with real fitment data, competitive pricing, and support from staff who understand performance and restoration builds. Filter by year, make, model, trim, engine, and drivetrain to confirm the correct application before ordering.

For focused shopping, browse our Fuel Injectors, Fuel Pumps, Fuel Delivery, In Line Modules, Exergy, AirDog, Sinister Diesel, Fleece Performance.