[HWYSTR455]

Ok, there were some questions regarding the Derale PWM controller, and dug into it more. It does not appear it has a start delay for restarts when hot, but you could if you wanted to wire a 'kill switch' if you wanted that feature.

The sensor is a stick-on type that is placed on the cool side of the radiator, I suspect due to the range it reads. It's possible too that it may not be able to handle over 300 degrees, or the housing, is why they do that, not sure. But suspect one could use a different sensor, a sensor within the same range, which appears to be 200k to zero ohms.

The Auto Cool Guy controllers are probably the best out there that I've come across, are potted so can be mounted in the engine bay, and are full featured. Wish they included a start delay feature, but not a show stopper. Maybe I just didn't see it.

https://www.autocoolguy.com

SPAL used to have a PWM controller, but it had so many issues and failures, they stopped making it.

Painless makes a PWM controller, the F5, and the folks over at Pro-Touring.com have been using them with great success:

https://www.painlessperformance.com/webcat/30140

Craig Davies has PWM controllers, also heard good things on other forums, worth a look:

https://daviescraig.com/switches-controllers-fan-ewp

I will be doing a little more homework on this coming summer, think I will dig more before I pull the trigger on a controller for my 'bird. When I checked my notes, they were dated, and figure it would be a good idea to update them.

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