89fast5oh

I have main primary fan to come on at 200 and turn off at 185. I've changed the cylinder head fan switch to a sw555. It still doesn't turn the fan on soon enough for my liking. With AC on it's getting to 215-220 in traffic.

I have a temporary wire spliced in with a alligator clip that I hook to ground to turn the fan on but I want something automatic/permanent.

I understand that grounding that wire activates the fan relay.

Is there something in the AC system I can splice into so that when I turn on the AC the secondary fan with come on?

BBCSwap

I have tried several different coolant fan switches and none of them turned the fan on & off at the temps they were supposed to. Some turned on the fan way to early and never shut off. Others turned the fan on 20 degrees higher than it show. Some don't turn on & off at the same temps consistently.

If you connect the two grounds from both relays won't that turn both fans on anytime one fan is activated? Would the more knowledgeable clarify this please?

89fast5oh

Connecting the relays together would cause both fans to come on, but I think that would create a huge currant draw and might overload things. That's why I'm trying to figure a out a way to stagger the fan start ups. I briefly searched for a delay relay and thought about wiring the fans together. Primary fan would come on then 10 seconds or so later the secondary fan would come on.