DPS 12V Cummins Compound Turbo Kit 1989–1998 Dodge Ram | 1st Gen & 2nd Gen Twin Turbo

12V Cummins Compound Turbo Kit | 1st Gen & 2nd Gen Twin Turbo System | 1989–1998 Dodge Ram

The Diesel Power Source® compound turbo kit is a complete twin turbo system for 1989–1998 Dodge Ram trucks with the 12-valve 5.9L Cummins engine. This kit covers both 1st gen (1989–1993) and 2nd gen (1994–1998) 12V trucks, with year-specific configurations selected at checkout. Each kit includes both turbos (S300 high-pressure and S400 atmospheric), a 3-piece high-flow exhaust manifold, all charge piping, oil lines, air intake, a 4" exhaust downpipe, and all hardware needed for installation. From stock power up to 1,100 HP, these sequential turbo kits bolt on with no cutting or fabrication.

Available in thirteen turbo size configurations ranging from 625 HP to 1,100 HP, with optional Turbonator® VGT upgrade for exhaust braking and faster spool, and optional ball bearing upgrade for 150–200 RPM quicker spool-up. Diesel Power Source® is the only company making compound turbo kits for 1st gen Cummins trucks.

The P7100 Advantage: Why 12V Cummins Trucks Are Built for Compounds

The 12-valve Cummins uses the Bosch P7100 inline injection pump, one of the most respected mechanical fuel systems ever put in a diesel truck. Unlike the electronic VP44 on the 24V trucks or the common rail system on the 3rd gen, the P7100 is mechanically controlled and responds to increased airflow with a directness that electronic systems can't replicate. When you add a compound turbo system that delivers significantly more air at cooler temperatures, the P7100 takes advantage of every bit of it with no ECM interference, no electronic derating, and no programming required to make power.

The P7100 is also one of the most upgradeable fuel systems on any diesel platform. Modified P7100 pumps with increased delivery, larger injectors, and adjusted timing can support the full range of compound turbo airflow from entry-level towing setups to 1,000+ HP competition builds. The 12V engine's simple architecture, combined with the mechanical P7100 and a compound turbo system, creates a platform with a nearly unlimited power ceiling and no electronic limitations.

1st Gen vs 2nd Gen: What's Different About the Kit?

This compound kit covers both generations of 12V Cummins trucks. The turbo system and manifold are the same, but the charge piping and intercooler connections differ between 1st gen and 2nd gen trucks. Select your year at checkout so DPS can configure the correct piping for your truck:

• 1988–1993 (1st Gen) with Stock Intercooler — Piping configured for the factory top-mount intercooler
• 1988–1993 (1st Gen) with Mishimoto 3.2" Intercooler — Piping configured for the popular Mishimoto upgrade intercooler
• 1994–1997 (2nd Gen 12V) — Piping configured for the 2nd gen intercooler and engine bay layout
• 1998 (2nd Gen 12V) — Late-model 12V with specific piping differences from 1994–1997

How Compound Turbos Work on a 12V Cummins

A compound (twin turbo) system uses two turbochargers working in series. The smaller S300 high-pressure turbo spools first at low RPM, delivering immediate throttle response that makes the truck feel alive from idle. As RPM and load increase, the larger S400 atmospheric turbo takes over the majority of the compression work, providing sustained airflow for high-HP applications without the lag that large single turbos create.

The two turbos share the compression work, operating within their most efficient ranges. The result is boost air that is over 100°F cooler than a single turbo at the same pressure, boost-to-drive pressure ratios approaching 1:1, and 250–450°F lower EGTs under load. For 12V owners who tow heavy with a 1994 Dodge Cummins, 1995 Dodge Ram turbo, 1996 Cummins turbo, or 1997 12 valve Cummins, the EGT reduction alone justifies the compound upgrade.

For a detailed explanation, see: How Do Compound Turbos Work? | Compound Turbochargers Explained

Stage Selection Guide

How to choose: Estimate your target rear-wheel HP, then multiply by 1.25. For a 12V Cummins built for towing and daily driving, Stage 2.5 through 5 covers most builds. The P7100 injection pump supports strong power levels with modified delivery and larger injectors. Sled pulling and competition trucks typically run Stage 8 or 8.5 with fully built fuel systems.

Turbonator® VGT Upgrade Options

Each compound kit can optionally include the Diesel Power Source® Turbonator® VGT exhaust housing on the S300 high-pressure turbo. The Turbonator® VGT is completely self-contained and works on all 12V Cummins truck years, including 1st gen trucks that never had exhaust braking from the factory.

• Base Option (Non-VGT) — Standard fixed-geometry S300 with wastegate. No exhaust brake.
• VGT Without Exhaust Brake (+$950) — Adds Turbonator® VGT for approximately 200 RPM faster spool
• VGT With Exhaust Brake (+$1,850) — Adds Turbonator® VGT with full exhaust brake capability on any year 12V truck

The exhaust brake option is especially valuable for 1st gen owners who have never had engine braking capability. It can also be combined with the ball bearing upgrade for maximum low-RPM response.

What's Included

• S300 High-Pressure Turbo (S362, S363, or S366 based on stage) with wastegate for adjustable boost
• S400 Atmospheric Turbo (S475 or S480 based on stage)
• 3-Piece High-Flow Exhaust Manifold with pre-tapped pyrometer ports
• Complete air intake with high-flow air filter
• Kevlar/Nomex lined silicone low-pressure charge pipe
• High-pressure metal charge pipe
• Cast hot pipe with external wastegate port (not welded thin steel)
• Support bracket for atmospheric (large) turbo
• Steel braided oil supply lines for both turbos
• Stainless steel oil drain lines (single drain on 12V engines — uses stock block oil drain port)
• 4" exhaust downpipe (included with 12V kits)
• V-band clamps, T-bolt clamps, and all hose clamps
• Turbo and manifold gaskets
• All mounting bolts, oil line adapters, and installation hardware

Key Features

• Complete Kit for Both 1st Gen and 2nd Gen 12V — Both turbos, 3-piece manifold, all piping, oil lines, downpipe, and hardware
• The Only 1st Gen Compound Kit Available — No one else makes a bolt-on compound system for 1989–1993 Cummins trucks
• Direct Bolt-On — No cutting or fabrication required
• 250–450°F Lower EGTs — Two-stage compression runs dramatically cooler than any single turbo
• 22–30% HP Increase — Depending on stage and supporting modifications
• Near-Stock Spool-Up — S300 lights up at low RPM, S400 carries top-end airflow
• No ECM or Programming Required — The P7100 mechanical pump responds directly to increased airflow
• Wastegated — Adjustable boost control on the high-pressure turbo
• Cast Hot Pipe — Not welded thin steel. Won't crack under thermal cycling.
• CAD/CAM and CFD Designed — Engineered for factory-like fit with optimized airflow
• Optional Turbonator® VGT — Add exhaust braking to any year 12V truck, including 1st gen
• Optional Ball Bearing — 150–200 RPM faster spool on the S300

Fitment

This compound kit fits 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, and 1998 Dodge Ram trucks with the 12-valve 5.9L Cummins engine (1st and 2nd generation). Select your year range at checkout so DPS can configure the correct charge piping and intercooler connections for your truck.

Automatic transmission note (1994–1998): 2nd gen trucks with the 47RH/47RE automatic transmission require the engine-mounted trans oil cooler to be removed, bypassed, or relocated to the frame for compound turbo clearance. A Trans Cooler Relocation Kit ($149) is available as an optional add-on at checkout. Manual transmission trucks do not need this modification.

These kits do not have a CARB exemption (exhaust manifolds do).

Have a different gen truck?

• 24V Compound Kit (1998.5–2002 Cummins)
• 5.9 Common Rail Compound Kit (2003–2007 3rd Gen)
• 6.7 Cummins Compound Kit (2007.5–2018 4th Gen)

Need a Fummins or Chummins conversion with compound turbos? DPS builds those too.

Head Stud and Fire Ring Recommendations

• Head studs recommended at 48+ PSI sustained boost
• Fire rings recommended at 55+ PSI sustained boost

The compound system is capable of well over 55 PSI but is fully adjustable. Follow proper torque specifications and break-in procedures when installing studs.

Why Diesel Power Source for 12V Compound Turbos?

Diesel Power Source® is the only company that manufactures compound turbo kits for 1st gen Cummins trucks. The 12V platform was one of the first applications DPS engineered compounds for, and these kits have been proven on thousands of 1st and 2nd gen trucks for towing, daily driving, sled pulling, and competition builds. Every kit is designed using CAD/CAM software and CFD testing for factory-like fit with maximum diesel performance.

• The Only 1st Gen Compound Kit on the Market
• Complete Kit — Everything in one box including 4" downpipe
• 13 Stage Options — From 625 HP towing builds to 1,100 HP competition setups
• CFD-Tested Airflow — Optimized piping and manifold geometry
• Bolt-On Fit — No cutting, welding, or fabrication
• Designed and Built in the USA

Related 12V Cummins Products

• Add-a-Turbo Kit for 12V Cummins (Uses Stock Turbo)
• DPS S300 Single Turbos for 12V Cummins (1989–1998)
• Compound Turbo Piping Kit (Bring Your Own Turbos)
• Trans Cooler Relocation Kit (1994–2002 Automatics)
• 24V Cummins Compound Kit (1998.5–2002)
• 5.9 Common Rail Compound Kit (2003–2007)
• 6.7 Cummins Compound Kit (2007.5–2018)
• Fummins Compound Kit
• Blog: How Do Compound Turbos Work?

• S362/68 over S475 - Max 625hp- Stg 2.5
• S362/68 over S480 - Max 650hp- Stg 3
• S362/68 Ball Bearing over S475- Max 625hp - Stg 3.5
• S363/68 over S475 - Max 650hp- Stg 4
• S363/68 over S480 - Max 675hp- Stg 4B
• S363/68 Ball Bearing over S475 - Max 650hp - Stg 4.5
• S363/68 Ball Bearing over S480 - Max 675hp - Stg 4.5B
• S363/73 over S475 - Max 700hp - Stg 5
• S363/73 Ball Bearing over S475 - Max 700hp - Stg 5.5
• S363/73 over S480 - Max 750hp - Stg 6
• S363/73 Ball Bearing over S480- Max 750hp- Stg 6.5
• S366/73 over S480 - Max 1100hp - Stg 8
• S366/73 Ball Bearing over S480- Max 1100hp - Stg 8.5

6 Reviews

• 5

  The best

  Posted by Marco on Sep 8, 2025

  Impressed w my twins turbos

• 5

  Compound Setup

  Posted by Steven S on Apr 25, 2025

  I have had your stage 2.5 compound setup on my 97 12 valve for a year now and I can say I am very impressed with how that really woke it up. 5x16 injectors and pump work, and 22 deg timing and can hold her to the floor with max fuel and the egts never go over 1100.

• 5

  5.9 Compounds

  Posted by Lance Dehne on Jun 19, 2023

  I had the compound kit on my 5.9 Cummins for 4 years now. It made a huge difference in towing trailers. It spools up quick for when I need to get the camper or the trailer moving from a stop. Also, it does not take a lot of effort to make a pass on someone when I'm in a hurry. I would recommend this kit to anyone, whether they want to play or work.

• 5

  Hello, I

  Posted by Greg P on Mar 31, 2023

  Hello,I do not normally comment on my truck part purchases, but I felt the quality of your kit was worth taking the time for. I recently purchased one of your stocker / S475 kits for my 06 ram. I have to say I am very impressed with the quality and packaging you guys do. This is my first compound turbo set up. I looked at many kits before purchasing yours. I looked at cheaper and more expensive. I had nearly talked myself into buying a cheaper kit. After receiving your kit I was immediately satisfied with spending the extra money on it. I opened the kit and was very impressed with the packaging alone. I thought to myself, if it performs half as well as it is packaged, I was going to be very happy. I had one issue after installation, but it turned out to be my fault for assuming. I assumed the tube from the output of the S475 to the input of my stock turbo was molded to the connector that uses V band clamp onto the S475. I had one extra clamp once installed and I thought it was odd, however I took the truck for a test ride and was very impressed with the faster spool up but the system got very loud and not as much boost as I had anticipated. I found out very quickly where the extra clamp went. After that mistake was remedied, the system is performing flawlessly. I am very satisfied with this kit. I look forward to putting it to the test towing in the Colorado mountains. I will be purchasing your intake for this same truck as well as probably upgrading my stock turbo to one of your new ball bearing turbos in the near future. I will not hesitate to recommend you guys to anyone who asks.

• 5

  Towing

  Posted by Michael Venter on Nov 26, 2022

  Best thing I could have done sooner was do compounds for my 6.7Cummins! Stock fuel with some items not on the truck and it tows awesome. Steep grades and EGTs issues are a thing of the past! Great kit

• 5

  98 12V

  Posted by Kenny M on Oct 28, 2022

  Hey fellas, did some upgrades after your compound set up. Hamilton stage 1 head, full manual valve body, 125 industrial injectors. Makes 683 hp and just under 1300tq at 7200 ft. Egts never get over 1100 no matter what I’m pulling or how I have my attitude adjusted. Tuned by grand by truck shop. This thing is a pulling beast. Thanks again.Â