MMM, I wouldn't trust the guage, Autometer have pretty sloppy standards, but I would hope it isn't 20 degree's out.
We returned a Autometer Tach that was reading 500rpm out (an a Clevo, we were changing gear at 8000rpm on the tach, but it was actually 8500rpm). We found out when we chassis dyno'ed the car, and had the dyno hookup, with their tach.
They sent it back, saying it was within spec! That tach is now serving duty in a "Fully Sik" Hyundai Excel now!
Not a bad effort for the original fan though! If the system is that efficient though, you may need a thermo fan to let it get to temperature.
We had to change the thermo on a mates ZA Fairlane, with a blown clevo in it, as the temp was still rising, with the fan on, with it sitting on 2000rpm in the driveway. They were setup to turn on at 85, and off at 80, and it cycles nicely now, temp at the start of the rad is about 80ish, and at the other end is 36 degree's.
Obviosly, your Radiator is working better than that, and your engine is creating less heat. Is the timing right?
