Im working on a new setup currently i have a Dual fan setup one is manual (Rocker switch) and one is auto @ 190'F (Temp switch), I have a second hole in to the water jacket in the intake manifold next to the current temp switch i was thinking about putting a switch around 210'F to 220'F in there to activate the second fan when it gets hotter.
Would this setup work well or not?


EDIT: The Relays are 40A so they should handle the fans nicely (I think).

 

Yes, as long as it's wired correctly it'll work just fine. This is what I did when I changed from a single electric to dual electric fan.

 

Here’s a schematic I found online for your spdt relays.