The Fan clutch has 2 speeds, fast and slow
With it on the faster speed, its feels like your driving with a trailer or 4 passangers compared to the slower speed. It feels like its sucking 50Nm :eek::eek:
It should only be on the faster speed while idling in traffic, or after you have just started the car, and it should only stay on for a minute or so. If its staying on the faster speed all the time then the clutch is stuffed, and its time for a new one (about $110 or so)
Dont think there would be much of a HP gain when changing to Thermos, but youll find the engine and airfilter wont get so dirty so quickly.