Underdrive pullys

[comet_666]

Does anyone run under drive pully's with a electric fan setup to keep voltage up? Forgive me if I am asking a dumb question.
Once in a while, only while at a light or stopped, my voltage goes from 14.5 or whatever and it fluctuates down to say 12.2 or 11.9 which causes a slight hiccup with my fuel injection. It started happening when I installed the brushless fan setup. I cant seem to recreate it on demand even if i sit in my driveway idling for 10 min, it's only once in a while.

Thanks!

[metallicareload99]

What alternator are you using? I got kinda the opposite problem, seems my water pump for whatever reason doesn't move enough coolant, but alternator and electric fans are working great. I'm running the biggest crank pulley I have with the smallest water pump pulley I have and it still gets hotter than I care for. I use a Denso 130 amp alternator

[comet_666]

Tuff Stuff 100 AMP; 1 Wire; Single Groove Pulley

[metallicareload99]

That "should" be plenty, but how much it makes at idle is the million dollar question. You are using a separate fan controller? The Fitech will raise idle speed when it's controlling the fans, might be able to tap into that feature 

[comet_666]

Yah i remember that when i had it inadvertently set to on way back when, I don't remember if it raised it or lowered it.
Its tagged into my dakota digital gauges  because the fans came with their own sensor.

[metallicareload99]

Another thing, what RPM is your idle? I do have my idle set kinda high (1050+ rpm) because of the roller cam and manual trans

[comet_666]

850 I think. If I set it higher, when I shut it off it likes to diesel