Preturbo 335i Strange Results

[rudypoochris]

Originally Posted by Richard L

Interesting project.

Water at ambient is about 1000 times denser than air. I can only assume the compressor is doing more work when methanol was injected on top of air. It is natural to require more energy (PWM) to accelerate a rotating mass.

How is methanol flow regulated (flow control), is it progressive with boost or engine load?

So basically the shaft speed may be less, but the work is around the same? Then really the turbo is seeing less "damage" due to overspeed but roughly equal thrust loading wear?

Methanol comes on at a boost switch set too low atm (8psi). It is not progressive at the moment, but I may switch it to be progressive with boost. The check valve makes it not progressive since the tank is pre-boosted to whatever the last pull left it at.

Are other people seeing reduced shaft speed or reduced work with pre-turbo meth?