DDP ISB-125 Stage 4 125HP High Flow Injectors for 1998.5–2002 5.9L 24V Cummins

Take your 5.9 Cummins to the next level with the DDP ISB-125 Stage 4 high-flow injectors. These Dynomite Diesel Products injectors deliver a strong 125 RWHP increase over stock and can support up to 520 RWHP with the right supporting modifications. They are DDP’s largest recommended street injector for 1998.5–2002 24-valve trucks.

These are brand-new, precision-matched complete injector sets (no core charge). They use SAC nozzles and are set at 290 bar pop pressure for reliable, high-volume fuel delivery.

Key Features

• Approximately 125 rear-wheel horsepower gain
• Fuel capacity for 475–525+ RWHP with proper upgrades
• New matched set — no core required
• SAC nozzle design
• Ideal for well-built street/performance 24V Cummins applications

Fitment

Fits 1998.5–2002 Dodge Ram 2500/3500 with the 5.9L 24-valve Cummins (ISB).

Required Supporting Modifications

Upgraded turbo(s) and a tuner are mandatory. Running these injectors without both will produce excessive smoke and unmanageable EGTs.

Recommended extras include a boost elbow (when possible) and appropriate fuel system upgrades. Some early 1998.5 trucks (engine serial number below 56462598) may also require new connector tubes.

Important Notes

• These are the largest injectors DDP recommends for street-driven trucks. Smoke output can be significant.
• A slight idle lope is possible, especially on VP44-equipped trucks or vehicles with modified pumps, oversized injection lines, or oversized connector tubes.
• Not recommended for P-pump conversions.

These injectors are built for enthusiasts who already have (or are adding) the necessary air and tuning support and want maximum street-legal-style power from their 24-valve 5.9.