on my rx-7 all i had to do was run 1 wire from the relay to a switch connected to ground in the cabin. Will this also work in the 8? if so where are the relays???

 

Not so simple....

There are two fans, A and B, one is larger than the other.
There are three relays that control them, 1, 2 & 3.
....but there are only two control wires from the ECU.
Wire "r/g" when grounded, runs fans A & B in series, (relay 1) slow speed.
Wire "w/l" when grounded, runs fan A alone, (relays 2&3) full speed.
Both wires grounded runs, predictably, A & B in parallel, (relays 1,2&3) full speed.

The relays are with all the other relays in the fuse box.

S

 

The same guy who just answered also has a DIY posted in the DIY Section.

You will need a zynther diaode as well

 

thanks, i read your other post but was a bit confused, the fd was easier, 2 relays, ground 1 for slow, ground both for fast.

 

If you can go 2 weeks without driving your car, the Racing Beat reflash would be an option. It keeps the car cooler with earlier fan activation, and gives a few extra HP up top for about $300.

 

I'm surprised that they don't always switch off when you're going over 30 MPH.

- (Or do thay?)