Adjustable Thermostatic Fan Clutch?

[ASMART]

This may not be the right forum but figured the most experienced/knowlegable would be in this forum. The ultimate fan seems to be elecitric but a thermostatic fan clutch seems to be the best combination of efficiency and simplicity. Is there a fan clutch that you can actually adjust the temperature or rpm that it kicks in at? I have found that there seems to be a standard that kicks in at around 170 degrees and rotates up to 75% or 80% of engine rpm. The heavy duty models rotate closer to engine speed and kick in at a lower temperature. It would seem that if you could adjust the temperature, rpm kick in, and % of engine RPM, you could come near the efficiency of electric with a much more simple install.

Thoughts??

 

[rbohm]

8) nice idea, but it would be much harder to build. an electric fan install is not that hard, and in the long run would be much easier to tune, and more efficient overall.

 

[wagon]

I have seen on some Toyota/Lexus models (LS400, V6 Camry(early widebody type) a hydraulically driven fan. I think this is a similar setup to those used on trucks, etc. for cooling hydraulic oil. The system may be adaptable to your application with a bit of solenoid control of the oil flow. However, I reckon electric fans are the go.