Product Description
Eliminate the failure-prone CP4 on your LML and step up to a high-flow CP3. The INDUSTRIAL INJECTION 436406 conversion kit replaces the CP4 with a 12mm Dragon Fire CP3 (120% over) and includes the brackets, lines, and components required for a clean, factory-style install. Built for high-fuel, competition-level power with the reliability the CP3 is known for. Custom tuning is required for this high-output kit.
Fitment
- 2011–2016 GM 6.6L Duramax LML (Silverado/Sierra 2500HD & 3500HD)
What’s Included
- 12mm Dragon Fire CP3 injection pump (≈120% over stock flow)
- Conversion hardware: brackets, lines/fittings, and install components for CP4→CP3 swap
- Harness/adapters as required by kit configuration
Key Features
- 120% over, 12mm stroker CP3 to support serious horsepower builds
- CP3 reliability in place of the known CP4 weak link
- Factory-style fitment for a tidy, serviceable installation
- Tuning required for proper fueling and emissions-system logic on LML
Recommended Parts (CPP Internal Links Only)
- AirDog Lift Pump Systems (LML options) — stabilize supply pressure and filtration for big CP3s
- AIRDOG A4SPBC191 FP-150-4G (2015–2016 LML)
- AIRDOG A4SPBC189 FP-150-4G (2011–2014 LML)
- Fuel Rails & High-Pressure Lines (LML) — smart refresh if your CP4 failed
- ARP 230-4201 Head Stud Kit (01–16 Duramax)
- Shop All GM Duramax Categories
Cross-Reference / Alternatives (CPP Internal Links)
- S&S Diesel LML-CP3-CARB Conversion Kit w/ Pump — 50-state legal, no tuning required street option
Helpful Notes
- This high-output kit is intended for competition/off-road builds. It requires custom tuning and is not CARB-exempt.
- If your CP4 has failed, inspect/flush or replace rails, lines, and injectors due to potential contamination.
- A quality lift pump (AirDog) is strongly recommended to protect your CP3 and improve consistency.
FAQ
Does this kit require tuning?Yes. The 12mm/120% CP3 flows well beyond stock and requires custom calibration on the LML for proper operation.
Is this emissions-compliant?No. This race-level kit is not CARB-exempt. For a 50-state legal option that keeps factory emissions and doesn’t require tuning, see our S&S LML CP3 kit linked above.
What horsepower can it support?Supportable power depends on your turbo, injectors, and tuning, but 120% over CP3s are commonly used in high-HP builds.
What else should I replace if my CP4 failed?Contamination can travel through the system; consider fuel rails, high-pressure lines, filters, and possibly injectors.
