I would guess it's a little less than that... of course, I'm not running LS1 fans.

Regardless, I've got them wired to a 40A fuse, and if they had a constant 40A draw on high, I'd pop the fuse when they go to high. (Always takes more amperage to go from a rest into motion than to keep something going). Plus my fans only have I think 16ga wire coming from the fan motor, so I would guess around 15 amp per fan running on high, peak at 17-18 at startup... That's just a guess though.

 

Is this a dumb idea for any reason:

Use the low trigger wire to turn on one fan and then the high trigger to turn on the other. Circuit for each fan is completely independent of the other. Basically 1 relay per fan and simpler wiring.

I guess to answer the question I have to ask another. How much cfm do both fans move on low (6v) and how much cfm does 1 fan move on high (12v)?

 

not dumb. That is perfectly acceptable. I had my fans set up like that when I had the flex-a-lites installed.

Don't know about cfm. Also don't know specifically which fans you are speaking of.

 

I'm talking about the stock truck fans, like what come on an 06 with the 34" radiator. Think a circuit capable of handling 30 amps would be sufficient for each?

 

WOW never knew of all these issues.. I have a nelson harness, the orig relays. Been working flawlessly for over 2 years now.. Sorry to hear alot of ya have had issue..

 

Ive probably posted this diagram 20 times on this site, but it really is not hard to make your own harness. I used cheapo relays, 12ga power wire, and 18ga single wire and this harness has worked flawlessly for 3 years with LS1 and the 05+ fans.

 

As it shows in the schematic that Atomic's posted, the factory harness has 40 amp fuses

 

This is the one I built after he posted it a couple weeks ago. Works like a champ.

 

Where did you guys get the socket connectors for the relays at? Ive seen some pigtails but they all have 14ga leads. I would rather get a bare connector w/terminals so I could use my 12ga wire. Or does it really matter that much since I would only have about 4in of 14ga coming out of the relay before it gets connected to my 12?

 

Got some off ebay and others I cut off the harness when I pulled the fan out at the salvage yard. You could use female spade connectors if you really wanted to.