Downpipe and turbine wheel whistle
 

This might sound like a dumb question, but do aftermarket downpipes make the exhaust turbine sound noticeable inside the car. The reason why is my buddy put a turbo xs downpipe on his wrx, and you can hear the turbine wheel spool inside the car. It sounded really sound so I was just wondering.

Thanks

The Evo doesn't seem to make a whistle regardless of the exhaust setup. I think it has something to do with an anti surge housing or the size of the turbine wheel. I could be wrong though.

Mine wasn't super audible with my stock turbo, now on my EFR 7163 it's very loud. I agree it doesn't seem to have anything to do with the downpipe though.

Appreciate the feedback

An intake will give you the sound your looking for. A downpipe to a test pipe and full exhaust will allow you to hear the turbo out the exhaust at low speeds if outside the car.

I did turbo back exhaust and ram air intake and there was no noticeable whistle, lots more woosh and psshh but no whistle. I swapped the stock turbo for an MHI 18K and now it whistles a lot, any time I'm accelerating beyond 3000rpm it is clearly audible if not loud.

That the anti-surge compressor cover, not the turbine.