6.7 Cummins Compound Turbo Kit | Complete Twin Turbo System | 2007.5–2018 Dodge Ram
The Diesel Power Source® compound turbo kit is a complete twin turbo system for 2007.5–2018 Dodge Ram 2500 and 3500 trucks with the 6.7L Cummins engine. 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, exhaust adapter, and hardware needed for installation. From stock power up to 1,100 HP, these kits bolt on with no cutting or fabrication and attach directly to the factory exhaust.
Available in six stage configurations to match your power goals, with optional Turbonator® VGT upgrade for exhaust braking and faster spool, and optional ball bearing upgrade for 150–200 RPM quicker spool-up. Select your model year at checkout and DPS builds the kit for your specific truck.
This kit is designed for trucks that have had EGR removal. Diesel Power Source® does not provide emissions delete components. These kits do not have a CARB exemption.
How Compound Turbos Work on a 6.7 Cummins
A compound turbo system uses two turbochargers working in series. The smaller S300 high-pressure turbo spools first at low RPM, delivering immediate throttle response and eliminating the lag that large single turbos are known for. As RPM and load increase, the larger S400 atmospheric turbo takes over the majority of the compression work, providing the sustained airflow needed for high-HP applications.
The two turbos share the compression work, which means each one operates within its most efficient range rather than being pushed to its limits. 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 (single turbos typically run drive pressure at nearly double boost pressure), and 250–400°F lower EGTs under load. This translates to more complete combustion, cleaner exhaust, more power, and significantly less thermal stress on the engine.
For a detailed explanation, see our blog post: How Do Compound Turbos Work? | Compound Turbochargers Explained
Stage Selection Guide
| Stage | Configuration | Max HP | Best For |
|---|---|---|---|
| Stg 5 | S363/73 over S475 | 700 HP | Towing, daily driving, strong all-around compound setup |
| Stg 5.5 | S363/73 Ball Bearing over S475 | 700 HP | Same as Stg 5 with 150–200 RPM faster spool |
| Stg 6 | S363/73 over S480 | 750 HP | Higher HP builds with more top-end airflow headroom |
| Stg 6.5 | S363/73 Ball Bearing over S480 | 750 HP | Same as Stg 6 with 150–200 RPM faster spool |
| Stg 8 | S366/73 over S480 | 1,100 HP | High-HP performance builds, sled pulling, racing |
| Stg 8.5 | S366/73 Ball Bearing over S480 | 1,100 HP | Same as Stg 8 with 150–200 RPM faster spool |
How to choose: Estimate your target horsepower at the rear wheels, then multiply by 1.25 to account for the compound turbo efficiency advantage. Select the stage that covers your target. If you are primarily towing and want the broadest usable power band, start with Stage 5 or 5.5. If you are building for higher sustained HP or competition, Stage 6+ gives you more top-end headroom.
Turbonator® VGT Upgrade Options
Each compound kit can optionally include the Diesel Power Source® Turbonator® VGT exhaust housing on the S300 high-pressure turbo. This adds variable geometry capability for faster spool-up and exhaust braking, which the base fixed-geometry S300 does not provide.
- Base Option (Non-VGT) — Standard fixed-geometry S300. No exhaust brake through the turbo.
- VGT Without Exhaust Brake (+$950) — Adds Turbonator® VGT for faster spool-up without exhaust brake function
- VGT With Exhaust Brake (+$1,850) — Adds Turbonator® VGT with full exhaust brake capability
The Turbonator® VGT is recommended for trucks that tow regularly and want the combination of compound turbo power with the exhaust braking they had on the factory VGT turbo.
What's Included
- S300 High-Pressure Turbo (S363 or S366 based on stage selection) with wastegate for adjustable boost
- S400 Atmospheric Turbo (S475 or S480 based on stage selection)
- 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 and cast hot pipe
- Support bracket for atmospheric (large) turbo
- Steel braided oil supply lines for both turbos
- Stainless steel oil drain lines and fittings
- 4" exhaust downpipe
- Exhaust adapter to factory exhaust
- V-band clamps, T-bolt clamps, and all hose clamps
- Turbo and manifold gaskets
- All mounting bolts, oil line adapters, and installation hardware
2010–2018 kits include a coolant reservoir.
Key Features
- Complete Kit — Both turbos, manifold, all piping, oil lines, and hardware in one box
- Direct Bolt-On — No cutting or fabrication. Attaches to factory exhaust, retains battery location
- 250–400°F Lower EGTs — Two-stage compression runs dramatically cooler than any single turbo setup
- 25–30% HP Increase — Depending on stage and supporting modifications
- Near-Stock Spool-Up — The S300 high-pressure turbo lights up fast, then the S400 carries the top end
- Boost Exceeds Drive Pressure — Compound efficiency puts boost-to-drive ratios near 1:1
- Wastegated — Adjustable boost control on the high-pressure turbo
- CAD/CAM and CFD Designed — Engineered for OEM-like fit and optimized airflow
- Optional Turbonator® VGT — Add exhaust braking and faster spool to the compound system
- Optional Ball Bearing Upgrade — 150–200 RPM faster spool on the S300 high-pressure turbo
Fitment
This compound kit fits 2007.5–2018 Dodge Ram 2500 and 3500 trucks with the 6.7L Cummins engine. Select your year range at checkout (2007.5–2009, 2010–2012, or 2013–2018) so DPS can configure the correct piping and adapters for your truck.
This kit is designed for trucks that have had EGR removal. Diesel Power Source® does not sell or provide emissions delete components. These kits do not have a CARB exemption (exhaust manifolds do).
2010–2018 trucks: An optional A/C Line Relocation Kit is available for trucks that need the A/C lines repositioned for compound turbo clearance.
Head Stud and Fire Ring Recommendations
As boost pressure increases, cylinder pressure increases proportionally. DPS recommends the following engine prep based on sustained boost levels:
- Head studs recommended at 40–45+ PSI sustained boost or when targeting 600+ HP
- Fire rings recommended at 55+ PSI sustained boost
Follow proper torque specifications and break-in procedures when installing head studs.
Complete Compound Kit vs. Add-a-Turbo Kit
DPS offers two compound turbo paths for the 6.7 Cummins. Choosing the right one depends on whether you want to replace everything or keep your existing turbo.
| Option | Includes | Best For |
|---|---|---|
| Complete Compound Kit (this product) | Both turbos (S300 + S400), manifold, all piping, oil lines, exhaust adapter, hardware | Full overhaul with matched components, highest HP potential (up to 1,100 HP), trucks starting from scratch or replacing entire turbo system |
| Add-a-Turbo Kit | Large S400 turbo, piping, oil lines, air intake (keeps your existing factory turbo and manifold) | Compound upgrade using stock VGT as high-pressure turbo, up to ~700 HP, retains factory exhaust brake |
Why Diesel Power Source for Compound Turbos?
Diesel Power Source® built its reputation on compound turbo kits. Thousands of 5.9L and 6.7L Cummins trucks are running DPS compound systems for towing, daily driving, sled pulling, and racing. These kits are designed using CAD/CAM software and CFD (Computational Fluid Dynamics) testing to deliver OEM-like fit with measurable performance improvements.
- Complete Kit — Everything in one box, no hunting for parts
- CFD-Tested Airflow — Optimized piping and manifold for maximum efficiency
- Bolt-On Fit — No cutting, welding, or fabrication required
- Wastegated — Adjustable boost for tuning flexibility
- Proven Platform — Thousands of compound kits sold across 5.9L and 6.7L Cummins
- Designed and Built in the USA
Need a Ford or Chevy Cummins swap with compound turbos? Check out our Fummins and Chummins conversion kits.
Warranty
This Diesel Power Source® compound turbo kit is backed by our standard warranty and technical support team for fitment, installation, and tuning guidance.
Related 6.7 Cummins Products
- Add-a-Turbo Kit for 6.7 Cummins (Uses Stock Turbo)
- HE300VG Replacement Turbo (Factory VGT, 2007.5–2024)
- T4i Exhaust Manifold for 6.7 Cummins (2007.5–2018)
- HE300VG Turbo & Manifold Package (Factory VGT Bundle)
- 3rd Gen Swap Kit (S300 Single Turbo Conversion)
- A/C Line Relocation Kit (2010–2018)
- Spin Lock Manifold Bolt Kit
- Blog: How Do Compound Turbos Work?
- 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
This complete compound kit replaces the factory turbo with an S300 high-pressure turbo and adds an S400 atmospheric turbo. If you want to keep your factory VGT turbo and add a large turbo to it, see the Add-a-Turbo Kit instead. Alternatively, you can upgrade the S300 in this kit to a Turbonator® VGT for variable geometry spool-up and exhaust braking while still running the full compound system.
The base compound kit uses a fixed-geometry S300 high-pressure turbo, which does not provide factory-style exhaust braking. If exhaust braking is important to you, add the Turbonator® VGT with Exhaust Brake option (+$1,850) at checkout. This adds variable geometry capability to the S300 for both faster spool-up and exhaust braking.
Head studs are recommended when running 40–45+ PSI sustained boost or targeting 600+ HP. Fire rings are recommended at 55+ PSI sustained boost. The higher cylinder pressures from compound turbo airflow put more load on the head gasket seal than a stock turbo setup. Follow proper torque specifications and break-in procedures when installing studs.
The complete compound kit replaces the entire turbo system with both an S300 and S400 turbo, a new manifold, and all piping. It supports up to 1,100 HP and is designed for trucks that have had EGR removal. The add-a-turbo kit keeps your factory turbo and manifold and adds a large S400 atmospheric turbo. It supports up to approximately 700 HP and can work with factory emissions equipment. Choose the complete kit for maximum power potential and a clean, matched system. Choose the add-a-turbo for compound performance using your existing turbo.
The ball bearing upgrade replaces the standard journal bearing in the S300 high-pressure turbo with a 360-degree ball bearing assembly. This reduces friction and allows the turbo to spool approximately 150–200 RPM faster. It is a worthwhile upgrade for trucks that tow frequently or want the fastest possible low-RPM response from the compound system.
DPS compound kits typically reduce exhaust gas temperatures by 250–400°F compared to a single turbo setup at the same power level. The two-stage compression produces cooler charge air and more balanced boost-to-drive pressure ratios, which results in more efficient combustion and significantly less heat. Many owners report EGTs staying under 1,100°F even under heavy towing loads where a single turbo would push 1,400°F+.
4 Reviews
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Solid upgrade for towing and playing
Installed a Sxe-363/S475 on my 2007.5 6.7L. This was a complete rebuild with 30% over injectors and a stage 4 custom cam from my local builder (this is basically a 98.5-03 profile to eliminate the EGR cam overlap). The kit was great quality and went together very easily. Coming from a BD SXE-364 iron horn with stock injectors to this....It is awesome. The pickup early in RPM is very nice and as the boost starts to build....hold on to your Tranny Input Shaft. The castings are finished well and all the hardware was included. The instruction were pretty good. I did have to make a bracket to mount the intake elbow to the body, but it was a pretty easy project. I wish the manifold had another port on the "downside" so in the flipped configuration I could install a drive pressure sensor and EGT probe without drilling. Also, I wish there was an airbox solution that didn't involve custom building to protect the filter from monsoon rains, but a lot of people run it this way. The oil feed lines are great SS braided lines, but the drain lines could be upgraded from the OEM style to A/N type. Solid upgrade to transform your truck into a better than stock drivable monster that TOWs. EGT's, what EGT's? I don't think I get them to 1100 unloaded without hitting the speed limiter.
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Hello, I
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.
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Towing
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
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Power Genius
Hello Power Geniuses, Just dropping a line to say great!! job.I purchased a compound kit for my 04 Dodge in July of 2014. Fantastic power & RELIABILITY !30k miles of driving & towing with a big smile on my face.Thank you for your knowledge & great products!
