DDP AFC Spring Kit for 1994–1998 5.9L 12-Valve Cummins (P7100 Pump)

Upgrade your 12-valve Cummins with the Dynomite Diesel (DDP) Air Fuel Control spring kit. This heavier AFC spring is designed specifically for the Bosch P7100 injection pump on 1994–1998 Dodge Ram 2500/3500 trucks.

When running larger injectors, the stock AFC spring often lets too much fuel in before the turbo builds boost. The result is laggy throttle response and heavy smoke. This DDP kit uses a stiffer spring to better match fuel delivery to available air, helping you keep the truck more responsive and cleaner under low-boost conditions.

Key Benefits

• Better control of fuel delivery at low boost
• Reduced smoke output when paired with big injectors
• Helps retain throttle response in performance setups
• Simple, straightforward installation
• Built for heavy-duty use

Important Fitment & Usage Notes

• Fits 1994–1998 5.9L 12-valve Cummins with P7100 pump
• Recommended only with injectors capable of supporting more than ~525 RWHP
• Not advised for stock or smaller injectors — it can hurt low-boost response and spool

This is a popular, inexpensive upgrade for 12-valve owners who have already moved to larger injectors and want tighter smoke control without sacrificing drivability.