GEMS - General Engine Management Systems Ltd - Forum

What wastegate duty for low engine speeds and loads would be recommended for a subaru road car if running open loop control?

Hi

For low engine speeds and loads i would suggest you don't close the wastegate it makes the driveability of the car a lot easier at low speeds as you don't keep getting big chunks of boost, i wouldn't start closing the wastegate until you hit 1600 - 1800 rpm.

I hope this helps, it is probably something worth experimenting with.

Phil

Cheers Phil.
But under low load conditions at say 3000rpm thare may be little boost available, small throttle changes may be required to maintain speed on the open road, but no boost needed. Would it be more efficient to have the wastegate open, or closed so if a fast throttle applied boost may come on sooner?

There may be little boost avaliable but you may as well use it, If you close the wastegate perhaps 70% then the boost will help the car maintain the speed, you have to take account of greater rolling resistances and drag at higher speeds.

This will also keep the tubo spinning and therefore enable boost to build faster when required.

I hope this answers the question.

Cheers for that
I'll give it a whirl.