Product Description

BorgWarner 177275 S300SX3 Turbocharger – S366/74, 0.91 A/R, T4 Housing

The BorgWarner 177275 S300SX3 (S366/74) pairs a 66mm extended-tip compressor with a twin-scroll 0.91 A/R T4 turbine for fast response and serious top-end air. Built on BorgWarner’s proven AirWerks S300 journal-bearing center section, this unit is a favorite for high-power single setups and as the high-pressure charger in S300/S400 compound systems.

BorgWarner 177275, S300SX3 S366 turbo, 0.91 A/R T4 twin scroll, AirWerks S300, CPP Diesel, diesel turbo upgrade, 66mm compressor, 73mm turbine, UPC 121A001489, GTIN 00121A001489

Key Highlights

• AirWerks S300 journal-bearing durability and serviceability
• 66mm inducer / ~91mm exducer extended-tip compressor
• Twin-scroll T4 0.91 A/R turbine housing for strong mid-range and top end
• Adjustable compressor/turbine housing orientation; 4.21" V-band turbine outlet

Fitment & Setup Guidance

This is a universal performance turbocharger. It is not a bolt-on for stock manifolds or downpipes. You’ll typically need a T4 manifold, appropriate oil feed/return (-4AN feed, -10AN to -12AN drain), a compatible downpipe for the 4.21" Marmon V-band outlet, and charge piping sized for the 3.0" compressor outlet. Commonly used on well-fueled 5.9L/6.7L Cummins builds and similar high-flow applications.

Cross-Reference / Alternatives (BorgWarner on CPP Diesel)

• BorgWarner 177284 – S300SX3 S366/74, .91 A/R, T4
• BorgWarner 177281 – S300SX3 S366/74, .88 A/R, T4
• BorgWarner 177283 – S300SX3 S363/68, .88 A/R, T4
• BorgWarner 177272 – S300SX3 S360/68, .91 A/R, T4

FAQ

Is the 177275 a direct bolt-on replacement?

No. It uses a twin-scroll T4 inlet and a 4.21" V-band turbine outlet. Most OEM setups require a T4 manifold, matching downpipe, and supporting plumbing.

What power range can this support?

Approx. 320–800 HP depending on engine, fueling, and tuning. It’s popular as a high-pressure charger in S300/S400 compound builds.

Do I need an oil feed restrictor?

Journal-bearing S300 units generally do not use a restrictor. Use a clean -4AN feed and a free-draining -10AN to -12AN return, and always verify oil pressure.

What’s Included

• BorgWarner 177275 S300SX3 turbocharger (S366/74, 0.91 A/R, T4 twin-scroll)

Why Buy from CPP Diesel

• Diesel-focused guidance for Cummins, Power Stroke, and Duramax
• Fast shipping and careful packaging
• Support for stock, towing, and custom high-power builds

Specifications for BORG WARNER 177275