Product Description
BorgWarner 177105 S400 Exhaust Housing — 83mm Turbine, T4 Twin-Scroll 1.25 A/R
BORGWARNER 177105 is a high-flow turbine housing with an 83mm turbine wheel, twin-scroll design, and a 1.25 A/R cast iron T4 divided-volute inlet. Engineered for durability, performance, and versatility in demanding turbo setups.
Key Specifications
- Turbine Wheel Size: 83mm OD, designed for high exhaust flow
- Inlet Flange: T4 twin-scroll divided inlet—boosted gas routing efficiency
- A/R Ratio: 1.25 (1.25 A/R) – balances spool speed and high-end exhaust energy
- Outlet Flange: 4-5/8″ exhaust outlet (Half Marmon or V-band depending on application)
- Material: Cast iron, built for high-temp durability and performance under load
Ideal upgrade housing for S400 or S400SX turbines. Requires matching components: exhaust flange, wastegate, manifold/external flange, and proper mounting hardware.
What’s Included
- BorgWarner 177105 S400 Exhaust Housing (83mm, T4 twinscroll, 1.25 A/R)
Recommended Add-Ons
Fitment & Use-Cases
Performance Street / Drag / Compound Builds: 1.25 A/R gives more exhaust flow for high boost, especially with larger displacement diesels or compound setups. Expect slightly slower spool vs 1.10 A/R but better top-end exhaust velocity.
Compatibility: Works with S400 / S400SX turbines, external wastegate setups. Confirm your exhaust manifold-to-housing flange, outlet size, and mounting clearances.
Shop Turbo Sections by Vehicle
Dodge/Ram Cummins
- CUMMINS MAIN HUB (Home tab)
- 1998.5–2002 5.9L (VP44) — Turbocharger
- 2003–2007 5.9L CR — Turbo/Supercharger
- 2007.5–2012 6.7L — Turbocharger
- 2013–2018 6.7L — Turbocharger
- 2019–2024 6.7L — Turbos & Accessories
Ford Powerstroke
GM Duramax
FAQ
Is the 1.25 A/R too large for daily drivers?
It depends on displacement, fueling, and desired RPM range. On smaller diesels or lightly built street trucks, spool will be delayed compared to lower A/Rs (1.10 or 1.00). But for high-boost, pull-heavy, or compound dual-turbo setups, 1.25 offers significant exhaust gas energy for top-end power.
Does this housing support external wastegates?
Yes. The housing includes provisions for external wastegate setups and is designed for users who want precise boost control. Confirm wastegate flange and size before purchasing.
Will this fit my S400SX / S400 turbocharger core?
Yes—this housing swaps onto S400 / S400SX turbine wheels, provided inlet flange (T4), outlet flange, turbine H-clip, and mounting hardware match. Always double-check wheel OD, housing geometry, and clearance.
Can I use this in a compound setup?
Absolutely. Many use the 177105 housing in compound builds as the high-pressure or exhaust housing when paired with a smaller spool charger or in dual turbo setups. Though pairing matters: you’ll want matching manifolds, gates, inter-turbo piping designed for your setup.
Do I need any modifications to use it?
May require exhaust manifold modifications, turbo stud changes, and ensuring your downpipe or exhaust outlet matches the Half Marmon or V-band connections. Fitment varies by vehicle and build.
Why Buy BorgWarner Turbos & Parts from CPP Diesel
- In-depth fitment support for Cummins, Powerstroke, & Duramax platforms
- Fast shipping & rugged packaging
- Authentic BorgWarner / AirWerks parts — no knock-offs
- Performance advice from diesel experts
