This is for Series 4 turbo (Gen II) 8.2:1 compression rotors only.
The factory casting of the series 4 rotor is drastically inconsistent over the 3 rotor faces, resulting in 3 different size combustion chambers on one rotor. This makes precise tuning impossible.
We CNC mill 3 new combustion chambers into the series 4 rotor, reducing the compression ratio to a uniform and repeatable 7.9:1. The combustion chamber shape is also modified with increased radius on the chamfer to increase flame travel in the combustion process.
Extra Options
When building an engine for circuit, drift or drag racing we highly suggest that you do all of the following to you rotor: