The 1989-1993 5.9L 12V Cummins is a mechanical engine with a VE rotary injection pump, no electronics, and no emissions equipment. The factory H1C turbo is the smallest and slowest to spool of any Dodge Cummins turbo, so more air is where these trucks gain the most. Diesel Power Source® builds turbos, manifolds, and compound kits for the D250, D350, W250, and W350, and is the only manufacturer with a bolt-on compound kit for 1st Gen trucks.
Mechanical Injection
No ECM and no tuner required. The pump responds directly to more air.
1st Gen Fitment
Built for the D250, D350, W250, and W350 chassis
Bolt-On Compounds
The only bolt-on compound turbo kit made for 1st Gen trucks
350-800+ HP Builds
From a daily driver single to a full compound setup
Upgrade Paths for the 1989-1993 12V Cummins
Daily Driver and Moderate Towing (350-450 HP)
An S362 or S366 single turbo with a fuel screw adjustment and a 3-inch exhaust.
Heavy Towing and Street Performance (450-550 HP)
A larger single turbo with pump work and a 4-inch exhaust. Compounds are a strong option here for towing.
Competition and High Power (550-800+ HP)
Compound turbos with a P-pump conversion and full pump build, a built transmission, and supporting modifications.
HP figures are approximate rear wheel horsepower and vary with pump work, fueling, and supporting modifications.
Why the 1st Gen 12V Responds So Well
The VE Pump Uses Every Bit of Air
The fuel screw, governor spring, and timing can be adjusted with hand tools, and the pump responds well to increased airflow. There is no electronic derating to work around.
P-Pump Conversions
Some owners swap the VE pump for a P7100 to support much higher horsepower. If your truck has been converted, tell DPS, because the turbo is sized to the pump and not to the model year.
Heat Is the Limit
A mechanical engine cannot limit itself electronically, so turning up fuel without adding air raises EGTs. More airflow is what keeps combustion temperatures in check under load.
Compounds on a 1st Gen
Two turbos share the work: the small turbo spools early and the large turbo supplies the top-end air. When sized right, compounds work at any power level, including a lightly fueled truck.
Before You Order
- Fits 1989-1993 Dodge D250, D350, W250, and W350 with the 5.9L 12V Cummins.
- Tell DPS whether the truck has the factory H1C or a different turbo, and whether it has an intercooler.
- Tell DPS if the truck has a P-pump conversion.
- S300 single turbos need a 4-inch downpipe on 12V trucks. It is sold separately.
- 12V heads have rectangular exhaust ports. Use a 12V manifold, not a 24V manifold.
Good to Know
- Expect roughly 10 HP per PSI of boost on a 5.9L Cummins.
- Head studs are recommended above 45 PSI of boost on 12V engines.
- The factory transmission typically needs attention around 400 RWHP.
- DPS S300 and S400 turbos are oil cooled. No coolant lines are required.
- Warranty coverage varies by product under the Diesel Power Source® PMA. Registration within 14 days of purchase is required.
Shop by category: 5.9 Cummins Turbos | 5.9 Cummins Manifolds | Compound Turbo Kits | All 5.9 Cummins Parts. Have a 1994-1998 truck? See 1994-1998 12V Cummins parts. Free shipping on orders over $350.
Cummins is a registered trademark of Cummins Inc. Diesel Power Source® is not affiliated with Cummins Inc.
