Dual Electric Fans on Carb'd Engine

[Neil B]

Originally Posted by rickpaw

Holley sells an AC on solenoid that bumps the idle speed up when the AC is on. You can use the fan on signal to trigger the solenoid. Holley P/N 46-74.

Just curious, why would an increased load on the electrical (with the fans on) cause the idle speed to drop?

From what I have read, that solenoid is not powerful enough to bump the idle on it's own. You have to blip the throttle and then the solenoid will hold it at the higher idle. So I'd have to blip the throttle every time the fans engage.

[gray86hatch]

Use a pwm to control the fan. On dads car with this you could not tell the fans were on. Almost never need to run at full speed.

On a normal drive on 80 degree day the fans dont come on unless stopped. I have the low at 195 and high at 205. Norm right on the tstat at 195

Tim