voltage dropping once second elec. fan is turned on

[metalmulishiaS13]

Ok, setup is rb25det greddy intake manifold, fmic, exhaust, STOCK basically. Anyways, I have two 12" Spal high performance pushers, one is wired into a temp probe from a 30 amp relay and 30 amp inline fuse. Then the same setup on the second, only that on is on a switch. After being warmed up, when I manually turn on the second fan, alternator is dropping below 13volts according to my safc2(don't worry not doing anything crazy, it was suppose to be a temp. solution till i got a pfc, since I have a z32 maf). Anyways, is there a way to fix this by maybe running a thicker gauge wire? I do mean to get the Quest alternator soon, but is there anything I can do in the meantime. I don't know if this would have anything to do with my idle problem, but entirely possible I suppose.

sorry for the long winded post. Thanks for any help.
Modified by metalmulishiaS13 at 2:10 AM 7/12/2009

[Joe]

the fan or alternator could be failing

you need to do an amperage test on both to verify output/input.

[metalmulishiaS13]

Thanks Joe, I would put more money on the alternator dieing. My 25 alt bearing seized up on me already, I am using a free rb20 alternator right now. However I have heard of one other person having a problem like this. Right now I just keep the revs up at 1200 or so and all is well.

It survived its third drift event today, but it is done a for a bit till I have more money.

[Carl H]

lol you named off the problem in your first post.spal fans while AMAZING fans and very well built/reliable units are very power hungry...you wont be ble to run both fans on standard alternator without some power issues.when i had spal hp pushers on my rb20 the standard alternator (80a) could barely keep the car running with the fans on, that is the reason I tried mounting the quest alternator in the first place as i needed more amps to drive the fans...works a treat now and gaurentee it will fix the power problems you're having.

[metalmulishiaS13]

awesome, I will def. get to work on getting the Quest in then. Cause yeah I forgot to mention in my first post, that this is only happening at idle, which is why I said I was raising the idle to 1200 to keep voltage up. I will let you guys now how it works out.

Oh on the another note, I actually bought those fans because a of post of yours a while back saying how well they worked. So I bought them. Other than the power problems I couldnt be happier with them.