is a performance-oriented, waste-gated turbocharger often utilized as a high-efficiency upgrade for heavy-duty diesel engines, most notably the Detroit Diesel Series 60 (12.7L) and Caterpillar C12.
This turbocharger hybridizes the high-flow capabilities of the S400SX (S471) series with the responsive, waste-gated design of the K31 platform.
Core Performance Features
Compressor Wheel Technology: Features a 71mm Forged Milled Wheel (FMW)—also known as a billet wheel—which is significantly more durable than traditional cast wheels. This technology resists fatigue and failure under high-boost conditions while improving response.
1.28 A/R Waste-gated Turbine Housing: Unlike many large-frame S400 turbos that are non-waste-gated, the K31 variant includes an integrated wastegate. This allows for quicker spool-up at low RPMs without over-speeding the turbo at high RPMs, making it ideal for stock plus applications where drivability and bottom-end power are priorities. 86x77 Turbine Wheel.
Extended Tip Technology (ETT): The compressor wheel utilizes extended tips to increase the effective diameter, which broadens the compressor map for higher pressure ratios and increased airflow without increasing the physical size of the wheel.
