Alt upgrade...

[diablostang]

What's a good upgraded alt for 94/95 stangs?

My battery keeps dying... I took the alt off the car, tested it at Advance Auto, and they said it was good. They also tested my (new) battery and said it was good. .. I'm pretty sure the reason it's running down is because I rarely drive this car very far, and I've got so much electrical stuff (HD e-fan, elec fuel pump, elec gauges, MSD setup etc etc)

 

[The Green GT]

I would have to say the 200 amp one, but Im not sure what brand. And If you have underdrive pulleys, Ive heard it might not work becasue the alt has to spin a certain RPM to even put out juice and at idle, wit UD's it dosent usually reach that RPM.


EDIT: Post some pics with the new wheels on. Even if you dont have the motor in yet. lol

 

[WHITE94COBRA]

Make sure to upgrade the wires going to and from the alt if you get a 200 amp, I switched to the 200 amp on my old 95 and fried the wires, I was told the cause was the stock wiring was too small for the added amps.

 

[95strokerPSU]

Have you checked the output while it's on the car running? Two months back I thought my alt took a crap on me, but Autozone tested it and it checked out fine. Turns out that when I had the alt bracket powdercoated I forgot to sand down the backside so the alt wasn't getting a proper ground. Just a thought.

 

[Therian]

Dave has a good point...I experienced this also.

another point before you spend 300 on a new alt...I was sure that my alternator was bad in my car...and I was ready to throw it in the garbage (I took it to three places to be tested...two said it failed, one said it passed ). Instead of being impulsive and buying a new alt, I took my battery to get tested...it came out good...HOWEVER...the battery turned out to be the problem as atleast one cell had totally ate the ****ter...it too was a new battery.

cliff note: try another battery and see if it happens still...and most places that test batteries and/or alts aren't incredibly reliable

 

[diablostang]

Hmmm... Lemme hear more about the powdercoated bracket one... I just painted all my brackets, and this is the first time I've run them like that. Where did you have to sand down?

My reason for not testing the alt on the car, is because I had open headers at the time (I was trailering the car) and didn't think people would be happy with me holding it at 2K RPMS... I guess I'll take it back tomorrow after I put the new exhaust on.

Thanks for the replies, I hadn't even thought of the bad ground because of brackets.

 

[HISSIN50]

I'd agree - the alt should be doing ok. For a seldom-driven car, I'd look for a draw that's killing the battery off between infrequent starts.

Good luck.

 

[diablostang]

Well, I think the problem is that I'm not driving it far enough between starts... I work 3 miles from home, and that's the furthest I've driven it yet... The rest of the times are just on and off trailer and in and out of shop... Only reason I haven't driven it further is I'm still breaking it in, fixing little probs, so I don't trust her any further away for now.

 

[mo_dingo]

I belive the alternator grounds where it touches the brackets. The bracket is bolted to the head which is grounded. So where the alt touches the bracket, sand it down.

2 other things to test. Get a DC amp clamp and see how many amps the alternator puts out at startup and after a few minutes (on the thick red wire at the alt).

Also, you should check to see how many amps is being drawn on the positive or neg. wire at the battery with the car off and everything turned off. Might have an excess parasitic draw on the system.

 

[95strokerPSU]

You want to sand down where the alt meets the bracket, but also where the bracket meets the head.

 

[diablostang]

Ok, I'll try those out, and see where we go.

Thanks for the help guys.

 

[gcomfx.com]

You want to sand down where the alt meets the bracket, but also where the bracket meets the head.

Good info. right here. I was just getting ready to paint my bracket.