Relay wire sizes

[snakeoil24]

Voltage drop only tells you if you are drawing system down not how many amps are demanded.

 

[Sonny]

I don’t have that tool so I guess I’m buying a 100 amp alternator.

 

[bearman]

If you go with the new alt make sure your pulley and wiring harness can handle the new load.

 

[snakeoil24]

Plus find out what it puts out at low rpm amperage!!!!

 

[snakeoil24]

Current alternator is a basic one from advance auto and is 60 amps. The fans draw 30. I have the fans driven off of the alternator, and now I have an MSD 6A ignition box wired to the battery. Condition still exists. It’s a basic car electrically, no power windows or doors, am radio, and lights. I read that going from a 60 amp to 85 amp alt doesn’t require a wire size upgrade. Sound correct? Would I need to go larger on the alternator?
Sonny

It likely puts out 6-10 amps if that at low idle

 

[bearman]

Sonny are your fans on all the time or do you have them hooked up thru a temp sensor. If you run them on all the time the alt will be running load power. If thru the sensor the amp draw will only happen when it reaches temp then will shut off. If you have a/c and use your fans as condenser fans your load will be different also. So before you just go buy a alt 100 amp do your homework. But the most thing is with everything on at idle what do you need for amp draw.

 

[bearman]

Late to the party anytime for me I upgrade something I always upgrade what's involved. Your fans will pull more load at a light because of that factor the alt wiring can't give you more amps. So upgrade is needed. Also next time your looking at the alt pulley did you use the old one or upgrade it to the amps that it should be. Some alt pulleys are different size. Better yet I should say each alt pulley is made to help produce max out put so if the new is 4 inch round and the old one is 6 inch round and you used old pulley on new alt it won't produce what your after. So between the wire being wrong and the pulley being wrong then your problem will never get cured. Good luck and just my 2cents.

Thanks

 

[Sonny]

Here is the alternator I bought from Summit. So much better.

 

[snakeoil24]

how many amp does it put out at idle

 

[bearman]

Look at the 8509rdsp7 high out put at low rpms. Has internal regulator which kicks in at lower rpms. Read more about this one before you buy one. It also is a tuff stuff product. The finish comes a few different way. The chrome one looks good and is a single pulley. Good luck

 

[snakeoil24]

nice looking 1 wire alternator how many amps at low speed does it put out??

 

[bearman]

Been digging into this as we are speaking. But from what I'm reading when it was built it for what most of us are needing. Fans, a/c and auto not to mention to keep all electronics in a safe zone and not overheat. As soon as I know more I will let you know.

 

[Nacho-RT74]

has being told the 100 amps alt from tuff stuff is able to put 60-5 amps out at iddle.

now... do you have the stock cluster ammeter still conected and working ? If you do, is wrong source anything from batt

 

[snakeoil24]

60-5??

 

[Nacho-RT74]

60-65 amps

next to consider... fan consumption. Yes relay says is able to handle 30 amps, but who says the fan sucks that load ? Relay is not a load sucker so despite the relay specs and check the fan specs. Modern fans are able to be handled on 16 or 14 gauge wires, and most on them get the pigtail made on that wire size. I don't think your fan will suck 30 amps really. I'd say more like 18-20 amps

 

[bearman]

I think everyone needs to add up total draw at idle to see what works best. Don't forget the shock treatment of fans kicking in and a/c clutch cycle produces most draw only for a few seconds but can be a load that the lower amp alt has trouble with. Again I need to pay attention to pulley size from alt to water pump to ps and crank. All must work together or overload or worse not enough pull out of alt. Also wire size very important. Just my two cents.

 

[snakeoil24]

if that alternator puts out 60-65 amps at idle you may need a electric idle adjuster and also 2 belts.

 

[bearman]

That's so true I agree.

 

[Sonny]

has being told the 100 amps alt from tuff stuff is able to put 60-5 amps out at iddle.

now... do you have the stock cluster ammeter still conected and working ? If you do, is wrong source anything from batt

I bypassed the ammeter by bolting the terminals together some time ago. Fans are hooked directly to alternator. MSD ignition off of battery.

 

[Sonny]

60-65 amps

next to consider... fan consumption. Yes relay says is able to handle 30 amps, but who says the fan sucks that load ? Relay is not a load sucker so despite the relay specs and check the fan specs. Modern fans are able to be handled on 16 or 14 gauge wires, and most on them get the pigtail made on that wire size. I don't think your fan will suck 30 amps really. I'd say more like 18-20 amps

I have dual 12” fans and the instructions said they together draw 30.