Originally Posted by DrCharles
Yep, sounds like we have a near-identical setup! My temp switch is nominally 195 but it's in the middle of the top hose (and the gauge is in the usual WP hole).
So it kicks in at 198 and brings temps down to 192 before it shuts off. On the highway on a hot day, though, it only comes down to 194 and won't shut off. Which is why I started this whole flail and didn't just leave well enough alone wink

I have ordered an Autocoolguy PWM controller, pricey but has a great reputation in reviews. Just didn't feel like spending the hours on the bench to make my own. It will definitely work better than the simple full-on or full-off relay I rigged up.

What pulleys are you using to get "somewhat" overdriven? The stock a/c pulley setup is either 1.3 or 1.4 depending on year, model, etc.
I would like to try 1.1 or 1.2 but I don't think such pulleys exist.


Wow that's wild, around 194 is where mine stays also. With the FiTech it's easy to change the fan on/off so my fans are off on the highway, but I "think" it should run cooler on the highway.

I'm using a stock repro crank pulley. My water pump pulley is some after market aluminum that was about a 1" maybe smaller compared to a stock style non-AC water pump pulley.

In the spring I'll see what a high flow 160 thermostat will do

Last edited by metallicareload; 09/14/20 02:19 PM.
440, 4-Speed, 3.54
1968, when Dinosaurs ruled the Earth