Product Description
BorgWarner 178789 S400SX Turbine Housing 1.10 A/R T4 Divided
The BorgWarner 178789 S400SX Turbine Housing 1.10 A/R T4 Divided is a genuine AirWerks replacement turbine housing designed for BorgWarner S400SX and S400SX-E turbochargers utilizing an 87mm turbine wheel. Featuring a 1.10 A/R ratio and twin-scroll divided T4 inlet, this housing delivers an excellent balance of spool-up, exhaust flow, and top-end horsepower for high-performance diesel applications. It is a popular choice for S475, S480, and other S400-based turbocharger combinations used in street, racing, sled pulling, and compound turbo systems.
Constructed from durable cast iron and engineered to BorgWarner's exact AirWerks specifications, the 178789 turbine housing helps maximize pulse energy, reduce drive pressure, and improve overall turbocharger efficiency. Whether you're replacing a damaged housing or upgrading an existing S400 turbocharger, the BorgWarner 178789 remains one of the most trusted turbine housing options available.
Features
- Genuine BorgWarner AirWerks S400SX turbine housing
- 1.10 A/R turbine housing ratio
- T4 divided twin-scroll inlet flange
- Designed for 87mm S400 turbine wheels
- Compatible with S400SX and S400SX-E turbochargers
- Cast iron construction for durability and heat resistance
- Improves exhaust pulse energy and turbine efficiency
- Excellent balance of spool-up and top-end power
- Ideal for single turbo and compound turbo applications
- OEM BorgWarner quality and fitment
Fitment
- BorgWarner AirWerks S400SX turbochargers
- BorgWarner AirWerks S400SX-E turbochargers
- S475 turbocharger applications with 87mm turbine wheel
- S480 turbocharger applications with 87mm turbine wheel
- High-horsepower Cummins performance builds
- Duramax diesel performance applications
- Power Stroke diesel performance applications
- Street performance turbo systems
- Drag racing and sled pulling applications
- Compound turbocharger systems
Note: Always verify turbine wheel size, inlet flange style, outlet configuration, and housing compatibility before ordering. This listing is for the turbine housing only and does not include mounting hardware, clamps, or gaskets.
What's Included
- BorgWarner 178789 S400SX Turbine Housing
- 1.10 A/R Divided T4 Volute
- Factory Cast Iron Housing
Specifications
- Manufacturer: BorgWarner
- Part Number: 178789
- Product Type: Turbocharger Turbine Housing
- Turbocharger Family: AirWerks S400SX / S400SX-E
- A/R Ratio: 1.10
- Inlet Flange: T4 Divided Twin-Scroll
- Volute Style: Divided Twin-Volute
- Turbine Wheel Compatibility: 87mm
- Outlet Style: V-Band / Marmon Style Outlet
- Material: Cast Iron
- Wastegate Configuration: External Wastegate
- Application: Single Turbo and Compound Turbo Systems
Cross Reference Numbers
178789, BWA-178789, 840232718409, 00840232718409, 178787, 178788, 178790, 168319, 171698, 177104, 177105
FAQ
Will the BorgWarner 178789 fit my S475 turbocharger?
Yes. The 178789 is commonly used with S475 turbochargers that utilize an 87mm turbine wheel and a divided T4 turbine housing configuration. Always verify wheel size and housing compatibility before ordering.
Is this a twin-scroll turbine housing?
Yes. The BorgWarner 178789 utilizes a divided twin-scroll T4 inlet designed to improve exhaust pulse energy and turbine efficiency.
What is the advantage of a 1.10 A/R housing?
A 1.10 A/R ratio offers an excellent balance between spool-up characteristics and top-end airflow, making it a popular choice for high-performance street, racing, and compound turbo applications.
Does this housing include clamps, hardware, or gaskets?
No. This listing includes the turbine housing only. Mounting hardware, clamps, and gaskets must be purchased separately unless otherwise specified.
What S400 housings are available as alternatives?
Alternative BorgWarner S400SX housings include the 178787 (.90 A/R), 178788 (1.00 A/R), and 178790 (1.25 A/R), allowing builders to tailor spool-up and top-end flow characteristics to their specific goals.
