is a bigger alternator indicated?

jerry S

New Member
Sep 3, 2003
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52.22N 5.12E
I have recently added an electric water pump, electric radiator fan, electric vacuum pump hooked up to the brake booster, and an electric fuel pump. I have a 60 amp alternator on the car right now. I have heard that MSD ignitions might not give enough spark at high rpm if the electrical system is under strain. Also, will this 60 amp alternator be able to handle the load at idle? So the question is; do any of the mustang mandarins suggest a bigger alternator? Is so, how much bigger?
 
I think it would be a smart move. You could probably get by with what you have, but more juice would be nice. Lots of people are swapping to the late model 3G alternators, you may want to check into that. Also, there are some hi amp GM 1 wire units available.
 
If you wanna do the GM 1 wire here's some info

Converting Your Ford GM Juice

# 1. Take the old alternator and regulator out.
# 2. Get the 94 amp 12si alternator out of an 84 Camero
# 3. Reclock the back of the alternator so the 2 prong plug is facing the right side of the engine compartment.

IMPORTANT make sure that when you take the 4 bolts out of the back of the alternator that you lift up on the case only enough to get it to spin!! Lifting it up any more than about 1/4 of an inch will result in the springs coming out of the contacts (this is a bitch to get back together) Re install the 4 bolts.


# 4. Get a 5/16 drill bit and drill out the mounting bolt hole to accomodate your original starter mount bolt.

IMPORTANT cover all of the openings of the alternator with tape so that the shavings dont get inside the alternator.

# 5. Make a new shim for the mounting bolt (will need to be longer than the original shim)
# 6. Connect a jumper wire (16 gauge) from pin 2 of the modular plug to the main post "BATT".
# 7. Connect the main post to the + side of the battery.

12sialternator.jpg


I used the original charge wire that was hanging out of the harness. Now that Green wire with the red stripe that used to go to the voltage regulator is a perfect +12V hot key on source for the duraspark mod and the fan relays!!.
 

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MustangMatt1966 said:
def. powermaster! great alternator..one wire hookup

I talked to PM. Their 100 amp alt. is about 1.5 inches deeper than a regular 65 amp alt. I have to be absolutely certain that it will fit my March Serp. Conversion kit and that includes my alt. bracket. After talking with the tech, he could not be certain it woudl fit.

Rbohm: when I detailed all the electric accessories, the tech said that my little 65 amp would just be under my actual requirements and that I would do just fine with a 100 amp, which would be just a little bit more than what I actually need. Enter PA-Performance. They have a 95 amp 3G alternater that has an identically-sized case as the oem alt. It has an output of 60 amps at idle and 120 max and comes in a nice blue powder coat. I think this is the way I will be going.


http://www.pa-performance.com/displ...)+Premium+Short&config4=60+Idle+/+120+Max&rP=