Hey guys! Got some electrical questions for y'all. Pretty much lowdown of the electrical setup. I have electric fans, water pump, fuel pump and vacuum pump (to help booster due to low engine vacuum). I had a Summit 100amp alternator on it, but with this supercharged big block when it would get warm here in Florida it would get up in temp. So my plan was to upgrade to these Spal fans off Summit.
Due to the upgraded amp draw from the fans, they recommended a 40amp fuse and relay per fan. I also have a aluminum shroud for the 14" fans that cover the whole radiator, which is a 28" 4-core Champion radiator. The v-belt is only spinning the alternator.
I have my battery located in the "back" (smugglers box of my El Camino), with 2 gauge wiring from the alternator to battery. I bought a Tuff Stuff 140 amp alternator
and am currently using the 1 wire setup to use my 2 gauge wires. I made a panel for the under side of my dash to move my relay fuses and distribution closer to the front and clean up my wiring, so basically the 2 gauge power wire from the alternator goes through a 100amp midi fuse, to a distribution block and the rest of the 2 gauge wiring goes to the battery. at the distribution block I have 3 10 gauge wires going to a separate small fuse block to power my lower amp fuel, water and vacuum pump. For the upgraded fans, I have an 8 gauge wire going to a 2 fuse box, that splits to 10 gauge wires going to the fan relays in the engine bay, and to be on the safe side we'll say its a stretch of 10' of wire (I have everything tucked). What concerns me too is the fan wiring that comes with the fans doesnt even look like 10 gauge, looks like 12. Wouldnt that cause a choke running that many amps across that long of a stretch from the fuse to the relay to the connector then drop from a 10 gauge to a 12?
So I talked to Spal about the fans and what their amp output was, and I was told at 13v each fan would require 19-21.5 Amps, which seems low for what the upgraded fuse and relay requirements they have are.
So anyways heres my issues. When I was burping my cooling system in park, when the fans kicked on they moved a **** ton of air, and actually dropped my temp down from 180 to 165/170°
which surprised me as ive never had that happen before, before with my old setup it would get to 180°
and stay there (granted if its not too hot outside). Later on went out to pick up pizza about 2 or 3 miles away, car drove great, but pulling in the lot at like 1000rpm slight gas, alternator v-belt started squealing (slightly embarrassing, but cant really hear over the exhaust lol) and when I stopped, I noticed my volts were at 12.5v. I assumed the v-belt needed to be tighter and was low voltage due to it slipping. Picked up the pizza and drove home with no other issues, when I'm cruising im at 13.8-14v on my volt meter. At home I tightened the belt and was going to drive it to work tomorrow.
Drove it to work about 15 miles away with no problems, stayed at like 175°
but again at idle after a little while I noticed my volts dropped again to 12.5v. Lunch time drove down to get more pizza about a mile with no problems. Driving home was about 88°
F outside, nice day, and I knew at this point that my voltage was fine til my fans kicked on. So at the eternal light I was at, I watched my temp get to 180°
and sure enough when I assumed my fans would kick on my volts dropped to 12.5v, and would fluctuate from that to like 13v, then kinda settle mid to high 12v. I put the car in neutral, about 900-950rpm and my voltage jumped back to about 13.8-14v. After a while of mostly stop as traffic lights here suck and my car at 12.5v at idle in drive, my temp started climbing to 190°
which i figured wouldn't happen cuz it was a nice day outside, but I assume its cuz my fans arent pulling their max amount if my alternator isnt putting out at idle what I'd like it to.
I get home, and put it in park and let it idle the temp dropped from 190°
, which leads me to believe the fans help cool the car fine, its just they need to be at 13.8v to be doing it. I had my partner help me while I tested voltage on the alternator pos to alternator case in park and drive. Park was 13.8v, drive was 12.6v. I tested pos and neg. terminals on the battery and same readings. Did a voltage drop test from the pos. alternator to pos. battery, was 0.1v, same for alternator case to neg. battery terminal. I was mid process of doing voltage drop from alternator to fans but I was so physically and mentally exhausted from how much I've been working at work and side jobs lately I had to go lay down and take a nap. So now I figured i'd post this and get your opinions and thoughts and what to test/look for. My other alternator never went this low, then again I didnt have fans as strong as these before. I need to get an amp clamp too to get a good idea of how much some of this stuff is pulling/moving.
Heres some pics of my gauges from the drive, first pic is in drive, second pic is neutral with slightly higher rpms and higher volts. (volt gauge is the top gauge on the 4 gauge piece)
Thanks for your help!