hey guys
i bought some LS1 dual electric fans a couple months ago and i think im finally going to put them on. my question is about the relay setup. Ive been looking around and i saw this relay made for dual fans, it looks simple and very adjustable.......anyone have any experience with other relay setups they liked?? the fans are being used on a stock radiator and a 454.

hey guys
i bought some LS1 dual electric fans a couple months ago and i think im finally going to put them on. my question is about the relay setup. Ive been looking around and i saw this relay made for dual fans, it looks simple and very adjustable.......anyone have any experience with other relay setups they liked?? the fans are being used on a stock radiator and a 454.relay are a nice safe cheap way to do it but i would go with the dc controller...

relay are a nice safe cheap way to do it but i would go with the dc controller...



i saw a webpage done by a member that used the LS1 fans and the dc controller and it looked easy enough, but why do you say go with the dc controller?? i know several people have said thats a good route to go, i was just wondering why you thought it was over the one i had in my link. thanks for the response.

What link?

thanks for catching that, i didnt even realize i didnt add the link. http://cgi.ebay.com/ebaymotors/DiF-2-DUAL-AUTO-ELECTRIC-FAN-CONTROLLER-S13-S14-SR20DET_W0QQcmdZViewItemQQcategoryZ33600QQihZ001QQitemZ110160511050QQrdZ1QQsspagenameZWDVW


im pretty sure ill end up with the DC controller, but i just wanted to see some peoples point of view before i bought anything.

I've never known anyone to use that one. That is problem #1 for me.

That spins the fans independently (see pot switches for each fan?). I'll still never understand that, even OEs. I guess you could use the manual lead for an AC switch if you use AC. I see no pic of temp sensor in that pic, so I don't know how that works. What is the ACC port for? Who makes it? Documentation?

Edit: Found it. http://www.frsport.com/_t_22.html

Looks like it might use a nissan sender. Nice install. :rolleyes:

Bonzo, the advantage to having two different temps for the two fans is that you can turn one on for your typical heat loads, and if that's not enough, then the second one will turn on. It saves load on the electrical system.

al5570, I don't really like that relay setup (from what I saw in the links) because it looks to me like it may not handle the power requirement of two good fans. Yes, it's nice to have the two temperature setpoints, but only if you are using an on/off relay.

If you go with the DCControls unit you will not need the two temperature setpoints, because the higher the temperature is the faster it spins the fan, so the second limit should never be reached. Plus, that relay unit is about the same price-why spend the same money on an inferior unit?

The other advantage to the DCC unit is that it does not "shock" your electrical system like relays would allow. If you didn't know, electric motors require three times their running current when they start up. When the relay switches on you may be pulling as much as 45 amps with that relay. Once it's running it'll allow 15 amps. Those numbers are per fan, according to the info in the links. When the second fan switches on you'll be looking at 60 amps, 45 to start the second one, and 15 for the already running one.

If you were to run a Mark VIII fan (single fan) you could draw up to 70 amps on startup, IIRC. The DCC unit allows a "soft" startup, since it ramps up the power. I don't know what the starting current is with it, but I think it is going to be less than the full on, running current.

I recommend DCC, unless you have to have it right away. Brian's shipping times are kind of slow and it's not easy to get a hold of him. If you've got some lead time (about a month, possibly less) and don't expect a quick (or any) response to emails then definitely go DCC. FWIW, I have heard that calls in the evening do get answered, so it's not like he doesn't bother.

If you've got to have it now you should probably go with a SPAL unit. Look for GMachinz here or on ebay, he can give you more info.

Personally, I don't like the SPAL unit, but that's because I feel the DCC one is far superior. The SPAL unit turn on full, like a relay, but then, once the fan is spinning, controls the speed in relation to the temperature. It has the ability to switch on a second fan, but that output is a simple on/off, again, like a relay.

I'd buy the SPAL over the relay setup, both for cost and function.

Just to clarify my comment. I understand 2 trigger points. But even GM changed it so at the lower temp 2 come on at 6 volts and at the higher setting (and A/C) both come on at 12v. They used 3 relays to accomplish that. Having only 1 come at a time is the part that makes no sense to me.

2 relay version: http://img.photobucket.com/albums/v359/SIBLY/Cars/fan_schematic_1995_TOP.jpg
3 relay version: http://img.photobucket.com/albums/v359/SIBLY/Cars/fan_schematic_1995_BOTTOM.jpg

I love my DCC. Some of the best $$ I spent on my car. Awesome piece.

http://img.photobucket.com/albums/v359/SIBLY/Cars/th_IMG_1236s.jpg (http://img.photobucket.com/albums/v359/SIBLY/Cars/IMG_1236s.jpg)

thank you very much for the input guys, based off of your guys comments and what ive read so far, ill probably be ordering the Dc controller.