[Nicks67GTO]

I'm looking for a nice alternator upgrade. I think my 40 year old stock one is getting weak. At cruise its only showing about 13 volts and my turn signals seem to bog it down under 12v.

I'm going to be running a decent stereo with an amp, Vintage Air, EFI, electric fuel pump and possibly electric fans in the future.

I need an internally regulated unit that will work with the stock wiring. My 455 and brackets are from a 73' i'm not sure if that makes a difference.

Are there any quick and painless alternator upgrades that I can get at a parts store?

[JC455]

If memory serves, try a Buick GN alt. from about 84-87. Should still be a 10SI case w/ int. regulator.

[David Jones]

I've had a Powermaster for a number of years. http://www.summitracing.com/parts/pwm-8002

[george kujanski]

Delco 12SI 94A from a mid-80's Camaro or such. Check out madelectrical.com for simple conversion info.

George

[bignate]

http://www.qualitypowerauto.com

[lust4speed]

Originally Posted by bignate

http://www.qualitypowerauto.com

Ron will probably answer the phone, and is the one you want to talk to. He's a car guy, and a very active member of our local all-make car club. If you don't see what you want on their website, give him a call and he can help you out.

That said, it sounds like part of your problem is old wiring and possibly bad grounds. While it would be the alternator's fault for not keeping the battery up to a higher voltage, turn signals dropping the voltage reading indicates a problem with the wires supplying the dash. Another way to look at it is while you see a voltage drop inside the car, turning on the turn signals won't hardly effect the voltage at the battery -- so problem has to be somewhere in the middle.

[HWYSTR455]

I've had the worst luck with alts, you can search for my threads, but to give you a recap, you can't run over 140a with v belts, and if you run a decent stereo, run a quality capacitor. Don't buy any auto parts store alts, 99.9999% are now junk, cores are all eaten up.

Bosch makes a brand new 10/12si alt, but they max at 94a, and found for me they weren't enough.

The PowerMaster 12si is the ticket, the part number I run is the 47294. Comes with a v belt and is a direct replacement for the 10/12si alts.

If you have a serpentine setup, call the vendor who made the setup and see about going to a denso style alt, and you can step up to a 200a.

The trick is to find an alt that makes good power at idle. It's rare a manufacturer show output across an RPM range, but some do. The powermaster one does make pretty good power at idle, and only under full load do I see them drop to 13.2 - 13.6 .

Choose your power-drawing add-ons wisely. Use stereo amps that are very efficient, like the new Kenwood Excelon XR amps. They use less power, don't spike, and require smaller power feed wires. Cooling fans that cool well draw big amps, usually more than 40a, some as much as 60a. Use a controller, preferably one that uses 'soft on' logic to prevent spikes.

Important: Don't terminate all your power-drawing accessories at the battery, you will cook your alt, and other items (like electronic distributors and ECUs) from spikes. All accessories should terminate where the alt lead terminates, which is usually the horn or voltage relay on the firewall. You should have at least a 10g or 8g alt feed wire. I know this is contrary to what you may have seen or heard, but believe me when I say, I know from school of hard knocks.

You can check this thread to get an idea how I addressed the common terminal issue:

http://forums.maxperformanceinc.com/...d.php?t=766541

When I get my car back from the body shop, I'm going to rewire and clean that setup up, it will be easier to route, add to, and troubleshoot if need be. That setup was basically a Picasso from learning along the way. I will do the whole thing in mesh braided cover too. EFI harness will pass through the firewall with an aircraft fitting, not that 3 foot in diameter stupid rubber thing all the companies use on their' harnesses.

One symptom when you don't have a common point is every time a high draw accessory kicks on is all the other accessories lose voltage. Things like EFI pumps and ECUs are sensitive to voltage, like think about the pump dropping to 13.2 volts under power when a fan kicks on, suddenly it will go lean. Not good.

.

[i82much]

I've had good luck so far with a NAPA reman 10SI, and I don't remember it being that expensive. Voltage is dead-steady 14 v at the gauge at a high idle (1000 rpm) b/c of the solid roller cam. I'd take your old one in to your local parts store and try and find a 10SI with the same clock position, I think they are 94 amps.

Disclaimer: My reman has only a year or so of limited runtime. HWYSTR455 probably knows an ass-ton more than I do about this, but if budget is a concern I'd give a reman 10SI a shot.

[Nicks67GTO]

So I checked out the Powermaster unit. Its a 140 amp Unit. If I upgraded to this part, don't I need to upsize the wiring? I've got a newer M&H engine harness.

[Nicks67GTO]

Originally Posted by lust4speed

Ron will probably answer the phone, and is the one you want to talk to. He's a car guy, and a very active member of our local all-make car club. If you don't see what you want on their website, give him a call and he can help you out.

That said, it sounds like part of your problem is old wiring and possibly bad grounds. While it would be the alternator's fault for not keeping the battery up to a higher voltage, turn signals dropping the voltage reading indicates a problem with the wires supplying the dash. Another way to look at it is while you see a voltage drop inside the car, turning on the turn signals won't hardly effect the voltage at the battery -- so problem has to be somewhere in the middle.

I will be sure to check the grounds. My fuse panel is also older and has had some strange issues in the past. In my future plans I intend to upgrade all my harnesses. I was going to possibly do that over the winter.

[PontGuy]

I went through big alternator problems with my TA last year and learned more than I ever want to know about them.

A generic 10SI from a local parts house will work for a basic car if you manage to get a good one. But I gave up after trying two of them and upgraded to a 94A 12SI Delco remanufactured alternator. According to the Delco tech site it has the most low RPM amps of any of the original-design early alternators. Problem solved, with overkill. And less than $100 purchased off the internet.

If you are really going to put a huge load on it then you will need to go with a later alternator or one of the aftermarket versions like a Powermaster. And also consider wiring upgrades as already mentioned.

I found this link very helpful: http://www.acdelcotechconnect.com/html/tas_alt_12si.jsp

[Will]

I can't be much help because I don't remember the specifics of where I bought it or who made the kit, but years ago I bought a kit that came with new windings and diode cluster for my original 10si alternator in my Formula that pumped it up to 90-something amps. Works great, still have the OE alternator, and was cheap. Maybe they're still available?

Alternators are really simple. You should rebuild your own (I'm speaking to anyone who might be reading this, not anyone in particular) next time you need a rebuild. All the bearings and other parts are available at low cost.

[TheCirque]

So a newer M&H wiring harness can't handle an upgraded alternator? And is that dash harness/fuse block AND engine harness or just engine?

[chrisp]

Stick with what you have and use a electronic voltage regulator instead of the mechanical type , will probably solve your light issue . I have some if needed , will accept your Delco cover as well .

[PontGuy]

The connection between the battery and the alternator was the one I was concerned with. Think about it, if the battery charge gets really low the high-power alternator will send all those amps down through the factory wire that is only sized for 1/2 the load. I added a heavy gauge wire from the battery+ to the alternator to take care of that.

The draw through the fuse box and stock circuits will not change so no problems there. Just be sure to make connections to high-power accessories that you add to the battery, alternator or other under-hood heavy direct feed (like the horn relay in early cars.) I'll leave it to others for advice on how to do this properly.

I agree that getting the power feed right is important to EFI and other electronic systems. At idle with the lights on, turning on the heater fan would literally stall my car. Not sure if the voltage drop was playing havoc with the Holley EFI that was on it then or the MSD distributor. Either way it was not good.

[grandville455]

Interesting thread, as I have had some alt issues too since switching to elecric fans, I run a dual fan set up from a stratus, and when i turn the switch on it pulls the gauge down and then back up, Now it's wired where both fans come on at same time, and with only 1 switch so i can kill it after burnout to make my run. I run a 94 amp one wire, would like something bigger, Funny thing is I have my old 63 AMP that I made a 1 wire by just using a jumper and it would drop less, and it didnt take near as much rpm to excite, this 94 amp I have is a factory 1 wire and have to rev it to 22-2400 to get it to charge after first starting it. I run a #4 welding wire from battery in trunk to alt, Not sure i want to spend 165 bucks tho, lol. I just spent 220 on a new yellow top optima, as my powervolt battery was 6 years old and on the verge of failing the load test.

[HWYSTR455]

Originally Posted by PontGuy

... At idle with the lights on, turning on the heater fan would literally stall my car. Not sure if the voltage drop was playing havoc with the Holley EFI that was on it then or the MSD distributor. Either way it was not good...

Exactly what I was talking about.

That Delco unit is pretty good, and the 'service vehicle' ones do provide a good amount of amps at idle. And pretty sure they are 100a. But I had 2 out of box failures on Delco alts, ones that said they were brand new, and when I got them it was obvious they were rebuilt. After that is when I switched to the Bosch ones, they for certain are new, but I needed at min 110a peak. So was forced to go to the 140a. If I sat in traffic with the A/C on and the fans kicking on, and the stereo was up past 1/4 volume, the battery would slowly drain, and eventually cut out (the car). Oh, another good point, use deep cycle batteries.

On the charge wire, on an M&H replacement ENGINE harness, unless you specify the upgrade, it comes with the OE size which I believe is 12g. The one they did for the clone I had them go to 8g or 10g, would have to look.

You would be shocked, no pun intended, if you were to take apart the dash harness side of the fuse block, and look at the connectors. The engine side is no better, and unless you've replaced it at some point, it's going to be a mess. And a job to clean up. Best advice, unless you have more time than money, just replace it.

Although it is common practice to run a wire right from the alt directly to the battery, that's not a good idea. As mentioned, at lest for high load stuff, a common point should be used, and should be where the alt feed goes directly.

Full headlight power passes through the firewall and the headlight switch. Some of those wires are only 14g or 16g, and they bake over time. So does the switch. Run headlight relays on the core support, and use the wire from the OE headlight switch to toggle the relays. Look at the MAD upgrade article for a good explanation, think the link I posted to the other thread has the URL.

chrisp - I think he said he already upgraded to an internally regulated alt.

When you buy the upgrades for rebuilding an alt, the ones that up them to higher output, all they do is overdrive the thing, and the power isn't 'clean' or consistent. Not to mention they usually burn out faster too. One of the big problems with the 10/12si rebuilts is the cases are boogered where the bearing gets pressed in, so they fail early. The other problem is the windings, which rarely is replaced.

CS130 alts overheat too fast, and cores now are just as bad as the 10/12si ones. Don't fall for the 'dual cooling fans' thing, they still overheat. The CS130s also have smaller bearings.

Nick, check the feed wire on the harness you got, see what size it is. Or if it wasn't purchased too long ago, call M&H and ask, they may be able to tell you. You could cut it open, replace the wire, and re-wrap it, it's just the one section that lays on the intake.

If you upgraded to an internal reg alt and got the harness for that, the alt feed wire goes to the horn relay. That makes things easy, that would be your common feed point/post.

I'm going to do a separate thread on an engine harness when the time comes to do the driver, and think I'm going to make a jig. That will make it easier if I needed to make another one, and will give folks an idea of how to DIY a harness. I figure that will be in roughly 6 months, once it comes out of the body shop.

I will have to start with a Painless or American dash harness to get the ATO fuse box, those are only available in bulk, and the manufacturers don't sell retail. The custom harness makers hold those boxes close to the chest, so not to impact sales of completed harnesses.

.

[HWYSTR455]

Originally Posted by grandville455

Interesting thread, as I have had some alt issues too since switching to elecric fans, I run a dual fan set up from a stratus, and when i turn the switch on it pulls the gauge down and then back up, Now it's wired where both fans come on at same time, and with only 1 switch so i can kill it after burnout to make my run. I run a 94 amp one wire, would like something bigger, Funny thing is I have my old 63 AMP that I made a 1 wire by just using a jumper and it would drop less, and it didnt take near as much rpm to excite, this 94 amp I have is a factory 1 wire and have to rev it to 22-2400 to get it to charge after first starting it. I run a #4 welding wire from battery in trunk to alt, Not sure i want to spend 165 bucks tho, lol. I just spent 220 on a new yellow top optima, as my powervolt battery was 6 years old and on the verge of failing the load test.

Try this: Terminate the cable that goes from the alt to the battery on a post under the hood, and run power for the relays for the fans to that post. I suspect you might have that already, just make sure all are on the same post. I used a ford sol as the common point, it works well.

Yup, one-wires are not the way to go, you can read all the why and why not at the MAD site, it all still applies. They work, just not optimal. They can spike too.

The opti yellow tops are what I run, just remember you need a 'smart' charger, and any short whatsoever cooks cells.

.

[grandville455]

Originally Posted by HWYSTR455

Try this: Terminate the cable that goes from the alt to the battery on a post under the hood, and run power for the relays for the fans to that post. I suspect you might have that already, just make sure all are on the same post. I used a ford sol as the common point, it works well.

Yup, one-wires are not the way to go, you can read all the why and why not at the MAD site, it all still applies. They work, just not optimal. They can spike too.

The opti yellow tops are what I run, just remember you need a 'smart' charger, and any short whatsoever cooks cells.

.

So run another wire from the back of the ALT to a ford solenoid and then run my power wires (#30 on relay)for fan relays to it instead of from a wire under dash correct? Or am I taking the cable off the back of the alt and that goes to one side of solenoid, then the cable that goes from alt to other side of solenoid along with the 2 # 30 power wires for relays? I have a smart charger i bought a couple of years ago

[HWYSTR455]

Ok, so the power feed to the fan relays are the #30 terminal. And do you have a remote starter solenoid? Like a Ford solenoid? It would be good if you use one, since it prevents the power wire to the starter from being live, only gets power when cranking.

So, the power lead to the sol from the battery is where you gang your accessory leads, and the alt lead. Not a separate wire from the alt, the only wire.

The power that feeds the relays for the fans right now is coming from the fuse box under the dash? If so, that's part or all of the problem.

Excuse my crappy diagram I pulled from the other thread, I did it in a hurry, but should give you an idea.

(that's an 8g wire for each bank of relays, not just one 8g)

.