What are the differences between STS, STS 55, and STS Advanced?
September 02, 2021 The STS (Superior Turbine Strike) turbine wheel will take a shorter time (a 5-8% decrease) to build boost, achieve higher top-end speeds, and extend the choking area. This is because it has less inertia and restriction compared to an 11 or 12-blade STD turbine, and it also has more flow capacity. The STS 55 turbine wheel improve from STS, inspired by cutting-edge turbine aero, employs a patent-pending splitter-blade design to achieve unprecedented levels of flow capacity and efficiency. This translates to a significant reduction in exhaust manifold pressure (EMAP) by operating at a reduced expansion ratio, unlocking a multitude of performance benefits:
- Unleashed Engine Power: Reduced backpressure, a direct result of the lower expansion ratio, allows your engine to breathe freely, resulting in a substantial boost in horsepower and torque.
- Enhanced Volumetric Efficiency: Lower EMAP, achieved through optimized expansion, improves the engine's ability to ingest air and fuel, contributing to heightened responsiveness and overall efficiency.
- Reduced Knock Sensitivity: Lower EMAP mitigates the risk of detonation, permitting more aggressive tuning and further power extraction.
- Cooler Engine Operation: The optimized expansion ratio contributes to lower exhaust gas temperatures, alleviating thermal stress on your engine and enhancing reliability.
The STS 55's innovative splitter-blade design transcends the traditional trade-off between flow capacity and efficiency. By refining blade loading and minimizing blockage in the throat area, it achieves the high flow of a low blade-count turbine while maintaining the efficiency of a high blade-count configuration.
The STS Advanced (Ceramic Dual Ball Bearing 9 Blades) enhances the STS (Journal Bearing 9 Blades) that improves the response speed (time needed to build boost) 10-15% as well as being more durable due to the improved shaft dynamics control. The increased power comes from the enhanced design. It utilizes an inner and outer race with rollers or balls between the two races. The inner race is pressed onto the turbo shaft, and the outer race is pressed into the CHRA. The rollers or balls replace the oil’s “job” of controlling the turbo shaft’s orientation but do still need to be lubricated.