Since the end last year, quite a few months after conversion of my BMW 318i from auto to manual, I have been looking at ways to improve the power output from the 2liter engine. Through the research the best way to see significant output is to force induce the engine, that is to force air into the engine instead of relying on the cylinders to pull air in.

Two ways to do force induction is supercharging or turbocharging. Chose turbocharging as it is more flexible in term of boost level. The target of this project is to run a relatively low and safe boost level. This means with stock internals and compression ratio thus the term softboost.

The earlier posts relating to OBD was due to the previous plan to control boost level using a wastegate solenoid and varying the boost depending on engine RPM. After the initial findings, it is concluded that there is too much latency between RPM of the engine and the one on interpreted by the microcontroller.

The engine to be turbocharged is BMW N42B20 in a facelifted BMW E46 chassis

Follow me through the journey of this project. Thanks for reading. All of this project related posts will be tagged with “softboost”