G Atsma

Depends on what's there already, but the wire from alternator to battery is what usually needs upgrading when kicking up alternator capacity.

rchavez101

Thanks for the info. I'm definitely going to upgrade the charge wire and will take a look at the rest of them.

sjsingle1

iTrader: (1)

upgrading the wires....big 3....involves not only the increasing the size of the positive wire....but also the ground wire....just so ya know

rchavez101

That is the plan.

TA_Freak

The powermaster 48237 DOES fit our 4th gen f-bodies. It's just a matter of re-clocking the rear housing 90 degrees clockwise and it fits perfect.

White94Bird

iTrader: (21)

Has anyone tried the Acdelco remain units one rockauto? 145 without a core and 145 amp 4 pin.

ReFtheMC

iTrader: (6)

I've never had any luck with reman anything, after 2 reman'd Alternators I went with a new 145 amp Duralast Alternator, 10 years and still going strong 👍

TA_Freak

Duralast, eh? I put my first Duralast 105A alternator on the TA around 300,000 miles ago and with the lifetime warranty, I've probably swapped them out a half dozen times. That 145A was the way to go apparently. I put the powermaster 220A recently and have not seen a drop under 13 volts since!

LilJayV10

iTrader: (39)

Do you remove the long bolts that hold the front/rear case together, rotate the rear case and bolt it back up?

I'm going to order that alternator today. I'm tired of my low voltage at WOT.

5.7stroker

iTrader: (36)

I’d consider the mechman 250amp hairpin alt also depending on what you are gonna need it for. For some of the larger fuel pump setups, the KG 145a isn’t enough

RB04Av

Yup, that's all there is to it. Don't pull it apart in the process; the brushes will pop out, and then you'll have to do more w... wo... wor... [pppppppuuuuuuuuuuuuuuuukkkkkkkkkke] sorry, can't bring myself to use such foul 4-letter words and inappropriate language...

LilJayV10

iTrader: (39)

What issue did you have?

I just installed it on my car and had zero problems. I didn't even have to re clock the housing.

Yeah she is a big girl, but she fits.

LilJayV10

iTrader: (39)

I got it installed and drove it this evening.

Did not fix my problem.

So that's 3 different alternators, one reman stock, one reman truck alternator, one Powermaster 220amp truck alternator
Big 3 upgrade
replaced L terminal connector.

Same result, 5500rpm, alternator stops charging.

To say I'm less than thrilled would be an understatement.

Y2K_Frenzy

What’s the catalyst to all these bum alternators? Under drive pulleys? Sound systems?

LilJayV10

iTrader: (39)

Stock diameter ATI balancer, stock diameter alt pulley, Katech manual tensionor, Gates belt.

It has a 750wx5 JL amp with 10 CDT sub.
Dual 525lph pumps.
Other than that the electrical system is stock 2000 Firehawk.

The radio was off last night when I drove it.

Last year I used an oscilloscope and monitored battery voltage at the battery and the L terminal at the alternator.

IIRC, the L terminal doesnt have a full 12v on it, I think if it does, it will burn something up. It's been long time since I read up on it.

I'm thinking running a temporary wire to the L terminal, with the needed resistors to drop the voltage down to whatever it needs to be, through a toggle switch and see how it acts.

In the instructions on the alt, it says it can be a one wire alternator. I don't know if it referring one wire on the 4 pin plug or just the big wire that goes to the battery. I don't remember seeing a way to "make it" a one wire.

RPM WS6

iTrader: (3)

I think most or all of the Powermaster units can be set up this way (one wire). What this means is that the only wire is the big (primary/charge) one. The upside to this is simplicity, but the downside is that you lose remote voltage sensing and the alternator is always "powered up" with field voltage as long as the battery is connected. The former (lack of remote voltage sensing) isn't such a big deal for the Powermaster as they tend to be built with enough voltage output to overcome this potential concern. But the latter (constantly powered up) is a bigger problem if the car sits for periods of time without being used (as this will drain the battery after a few weeks).

I have my '71 set up this way (one wire, Powermaster); it's an older 10SI style unit but the principles are the same. Someone had already modified the harness for this prior to my ownership, otherwise I would have kept the original multi-wire configuration. I don't have any low voltage condition, even without the remote voltage sensing (again, because Powermaster is a quality unit with great output), but I do have to disconnect the battery when the car is not in use because of the drain of constant field voltage in this arrangement. I only drive the car maybe once per month in the on-season, so it would be very hard on the battery to leave it connected all the time in this configuration.

LilJayV10

iTrader: (39)

At this point I'm not sure what direction to go. There is obviously some issue with the car. It's a pretty simple system, I'm not sure what I have overlooked or have done wrong.

LilJayV10

iTrader: (39)

I wanted to come back in here with an update.

I've changed back to the stock OS(upgraded 2 bar) and that took care of the problem. I had been using a Tahoe FF tune since last fall. The car never drove as well on the Tahoe OS, for whatever reason.

This afternoon I went back to the stock OS because I started logging airflow follower/cracker PIDS to try and fix the problem of it not returning to idle correctly. I found absolutely no cracker activity and very little follower activity, even though I had put those tables back stock using the F body values.

After going back to the 2bar Fbody OS, I had a lot of follower/cracker actiivity and you know what?

It holds 13.8v all the way up now.

When I went to the Tahoe O/S, in the SYSTEM>GENERAL>SYSTEM OPTIONS tab, I changed those to match my stock OS. With the Tahoe O/S, my dash was lit up like a Christmas tree which always bothered me. With me having to scale my tune for the injectors, the FF adder spark table was really of no use to me because you can't rescale the adder table. The only real benefit was the sensor itself that would change the stoich value.

For me, for a long list of reasons, will be sticking with the 2bar upgraded OS and get a Innovate WB setup that shows ethonal content so I can change the stoich value in the tune if needed.

I did go back in the logs(I log it almost everytime I dirve it) and verified with the stock alternator and cables, it stopped charging around 5500rpm. It did it with the Big 3 upgrade too.

Why it acts the same way with the Tahoe OS, even with the aftermarket alternator I don't know and at this point I don't care.

RPM WS6

iTrader: (3)

^ Interesting update, that's not something I would have expected but I guess it shouldn't be too surprising considering everything else you have already tried.

"Once you have eliminated the impossible, whatever is left, however improbable, must be the answer."

It's great that you got it fixed. I once had a very odd charging issue with my '98 Z28, tried tons of fixes/diagnostics to no avail, and ended up with a solution that some folks insisted "couldn't possibly have been the source of the problem" - yet it solved the problem, and it has stayed solved for nearly 20 years. LOL.

Glad you've got it working now. I understand how frustrating it must've been, and how rewarding it feels when it's over.

LilJayV10

iTrader: (39)

I ordered a Holley EFI alternator connector/wire with the resistor and was going to hook it up to a switch 12v next. That probably would have fixed it, but I would have never known what the issue was.

When I changed the OS, in the back of my mind I was "hoping" it would somehow fix the issue but wasn't that hopeful.

But honestly, unless there was something wrong with the PCM, there was literally nothing else it could be.

Working on a problem on and off over months, it's easy to lose track of what you have done and when. Luckily I datalog a lot and I'm able to go back and look.

I am really big on diagnosing and figuring out a problem instead of just throwing parts at it and see what sticks.

I don't feel bad about spending $400 on an aftermarket alternator anymore, even though there is a good chance that the reman truck alternator would have fixed the issue.

Regardless I'm happy it's over, lol.