Originally Posted by Oddjob

I've always installed as shown in the 21-12a figure posted above. Had a Porsche dealer tech point that out to me 25+ years ago, saying it goes in backwards to how most people want to install it.

I did remove one on a street car one time, because I thought it might be failing (turbo water pump was running constantly, turned out to be a bad temp sensor). Car would not get up to temp in moderately cool weather, not warm enough to blow heat when wanted/needed in the cabin. So I'd recommend running the turbo therm on a street car, unless in extreme hot climate conditions.

I have run without one on my track car, because I'm always racing in warm weather and running the car hard, so no worry about the car not warming up.