71stingraybigblock

I am about to get started on installing dual spal fans and was wondering where you guys decided to mount your relays and how you ran the grounds?

My intitial thought is to mount the relays under the passenger side dash and with our cars being glass, run the grounds directly to the negative battery terminal. Thoughts? Opinions?

Thanks

redwingvette

I don't have the dual fan setup but for the fan I have I grounded to the rad support. I mounted the relay to the wheel well and pulled power from the horn relay. The only wires going into the cockpit is for the switch I use to turn it on. Teh fans draw a;ot of power so the relay uses a 10 gage leed from the power source the relay and then to the fan motor. The power to turn the relay on can be 16 gage. If you use a temp switch to turn it on then you can pull power from the horn relay, to the fan relay, and then to the switch.

R. Bruno

I haven't installed mine yet, but I was going to mount the relays in the engine compartment against the drivers side firewall, and run the ground to the frame or radiator support.

JRODDVETTE

i also have the dual spal fans. i mounted my relays on the passenger side of the engine compartment and ran the grounds straight down to the frame.
i took power from where the battery cable connects to the starter.

bb Blue 73

Have mounted the relays on the drivers side firewall with the power wire going over to the positive terminal on the starter and grounds being connected to the block. Don't know if I will run a wire into the interior to manually turn them on or not. Was thinking about putting a cutout switch in the interior so only one fan will turn on with the thermostat and the other stay off. Will have to see if both running at the same time in cooler weather is worth the noise.

71stingraybigblock

Thanks Guys. I like the idea of keeping everything under the hood, mounting relays to the firewall, grounding to the frame, and running the hot wire to the starter. I may go this route.

R. Bruno

If you go this route- I don't know if you have an integral regulator within the alternator. If so, consider mounting a power distribution block on the firewall to draw power. I did this and it worked great. Go to madelectric.com and you can get the distribution block ($4 I think) and advice from the owner Gary (I think) on how to do this. This guy was great. He helped me through it on a SUNDAY afternoon.

71stingraybigblock

Thanks R.Bruno

EDDIEJ82

I mounted mine on the drivers side and pulled power directly from the positive bolt on my alternator, I ran my switched wire to the windsheild wiper wire. It all went through the wire loom and It is only a short hop to the back of the alternator. I grounded the fans to a bolt on the front crossmember holding my brake lines in place. Maybe I'm just weird the way I wired it but it works Perfectly and its almost invisible

marioncole

I just stuck the relays behind the dash on passenger side. I used the IGN terminal on fuse block for the relay lead and spliced into a ground wire behind the instrument console that is used for grounding the the componenets in the center console. I ran the heavy hot wires with fuse blocks on them under the carpet on passenger side back to the rear through an opening in the body to the center compartment and over to the battery compartment. I connected them to the positive terminal of the battery using a slightly longer battery terminal bolt. The temp sender on lead for the relays was run to a temp sender I installed in the left head. The hot leads from relay to fan were run from the relays through a hole I drilled in the firewall on the passenger side (and fitted with a gromet) over to the driver side fender and down to the fan harness. The groud wire of the fan harness was attached to the stud on the Radiatort support frame that used to hold the bottom of the fan shroud.

Schmucker

I'm going to stick my fan relay on the driver side inner fender in front of the cruise but behind the alternator. I pushed the wire for the ignition power through the rubber grommet holding the vacuum lines that go to the switched. I'll ground to the rad support. I'll get my battery power off the battery lead on the alternator.

71stingraybigblock

The info you guys are giving me is helping a great deal in mapping this out. Last night I decided to mount the relays under the passenger side dash (instructions recommended interior mounting) and I ran the wiring to a pre-existing grommeted hole in the firewall. This hole has some wiring and the oil pressure line, but enough room for the fan wiring and using the grommet. That is as far as I got.