Weistec ASV/WM Injection System

The Weistec ASV/WM Injection System is designed to enhance the performance and longevity of the M157 BiTurbo 5.5L engine. The system incorporates a Weistec Anti Surge Valve (ASV), addressing a factory omission where the M157 engine lacks a bypass valve. Without this, turbochargers are susceptible to compressor surge during rapid throttle closure, a condition that can lead to damage and diminished performance. The ASV actively manages this by venting compressed air using engine vacuum when the throttle closes, creating the characteristic blow-off sound while protecting the turbochargers. Complementing the ASV is the integrated Water/Methanol Injection (WMI) System. This technology, proven in aviation and motorsports, leverages the cooling effects of water and the knock resistance of methanol to significantly increase horsepower and torque while reducing the risk of intercooler heat soak. The WMI system features a progressive controller with a built-in MAP sensor, ensuring smooth, boost-dependent injection. The included Turbo Charge Pipes are equipped with bungs for dual injectors, promoting uniform air-fuel mixture and cooling. Key features include reduced intake air temperatures, increased knock/detonation resistance, and a claimed potential for up to 100 HP gain. The kit includes red powder-coated turbo charge pipes, Weistec Anti Surge Valve(s), a vacuum/boost adapter, a water/methanol controller, dual injector bodies with check valves, various nozzle sizes, and a trunk-mounted 2.25-gallon tank designed to fit in the spare tire well for a hidden installation. It is designed for a 50/50 water and methanol mixture and is compatible with stock, W.3, and W.4 turbochargers. This product is not legal for sale or use on pollution-controlled motor vehicles in the United States. Vehicle application data indicates fitment for specific Mercedes-Benz SL500 Roadster (R231) models with the Twin Turbo 4.7L V8 (M278) engine from 2015-2020.