Dan-pa, this is a street rod with a 350 small block Chevy engine and a 2004R trans. The trans is cooled by a cooler from Bow Tie Overdrives mounted in front of the radiator. The radiator is an aluminum unit from Speedway Motors and it keeps the trans temperature below 140* even on 100* days.
There is a 180* thermostat in the engine, so with a fan switch that switches on at 180* once it comes on it would run continuously. Right now it has a thermo switch and relay from Painless and it switches on at about 195* and off at about 185*. Because the thermostat and switch off temperatures are essentailly the same, given the slight inaccuracies of those devices, the fan sometimes never goes off once it comes on even though the temperature is at the 180* maintained by the thermostat.
That is why I'm looking for a switch off temp of about 190* to create a gap between the thermostat minimum temp and the switch off temp. There will probably be a little bit of trial and error in this.
What kind of switch did you find to install in the radiator lower tank? That is intersting because that is probably the coolest place in the cooling system. I actually thought of relocating my thermo switch from the intake manifold near the thermostat (a hot spot) to the water pump (a cooler spot).
Thank you for the suggestion.
