Product Description

BorgWarner 177102 S400 Exhaust Housing — 83mm, 0.90 A/R T4 Inlet

BORGWARNER 177102 is a cast-iron exhaust housing designed for S400 turbine upgrades. It matches up with an 83mm turbine wheel, features a 0.90 A/R twin-scroll volute and uses a T4 twin-scroll inlet. Ideal for boosting flow in S400 systems whether you’re rebuilding or upgrading.

Key Specifications

• Wheel Compatibility: 83mm turbine wheel OD
• A/R: 0.90 (balanced for faster spool and efficient midrange flow)
• Inlet Flange: T4 twin-scroll / divided inlet
• Outlet: usually V-band or half-Marmon depending on setup (verify plumbing)
• Material: Cast iron, high temp OEM-grade

Make sure your turbine housing matches your manifold flange type and downpipe/orientation. Proper sealing and wastegate matching are critical for performance and reliability.

What’s Included

• BorgWarner 177102 S400 exhaust housing (83mm, 0.90 A/R, T4 inlet)

Recommended Add-Ons

• CPP S400 Turbine Housing Gasket Kit
• CPP S400 Divided T4 Manifold Upgrade
• CPP S400 Wastegate Flange Kit

Fitment & Usage Notes

Rebuild Compatibility: Works with existing standard S400 turbine wheels (83mm) if you’re replacing or upgrading housing only.

Compound Builds: Use this housing when pairing with a matching compressor or atmospheric turbo in S300/S400 compounds to fine-tune exhaust flow.

Street vs Track: .90 A/R is a great middle ground: faster spool than larger A/R, less restriction at higher power. Excellent for street driven high-output and moderate compound setups.

Shop Turbo Sections by Vehicle

Dodge/Ram Cummins

• CUMMINS MAIN HUB (Home tab)
• 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

• Powerstroke — Turbochargers
• Powerstroke Parts Hub (7.3L / 6.0L / 6.4L / 6.7L)

GM Duramax

• Duramax — Turbochargers
• Duramax Parts Hub (LB7 / LLY / LBZ / LMM / LML / L5P)

FAQ

Will this housing work with my stock S400 turbine wheel?

Yes — this housing is designed for an 83mm turbine, which is common in many S400 setups. Just ensure your current turbine wheel OD and intake manifold alignments are correct.

Do I need a different wastegate setup?

Possibly. Because of the twin-scroll T4 inlet and .90 A/R volute geometry, wastegate flow and placement become more critical. Consult CPP for matched wastegate or external flange options.

How does .90 A/R compare to larger A/R ratios?

.90 A/R gives quicker spool and better midrange response than a larger A/R (1.10, 1.25, etc.) but slightly less top-end flow. If your power goals are extreme HP, you may want larger A/R housing, but .90 is great balance.

Is the inlet T4 divided twin-scroll universal?

While many S400 setups support T4 twin-scroll inlets, verify manifold flange style. The divided inlet path is essential for twin-scroll behavior.

Can CPP help set up matching turbine housing and exhaust manifold combos?

Yes — we assist customers in spec’ing manifold, downpipe, housing, and gates for the desired power and spool goals.

Why Buy BorgWarner Turbos and Housings from CPP Diesel

• Real fitment guidance for Cummins, Powerstroke & Duramax platforms
• Fast shipping and secure packaging for turbo components
• OEM-grade castings and matching components for long life in high-boost environments
• Phone & chat support from diesel performance specialists