Higher output alternator

[Knebel]

I tried the search but somehow couldnt come up with anything....

I am looking for an alternator which has more output at idle. With my EFI, Electric fan and lights on i see 11.8Volts at an Idle and after shutting the car of when taking short drives, I have a hard time starting it....

Are there any "drop in" alternators which have 2 wires (the Charge wire and the FLD wire) and have higher output at Idle? I dont mind if its 60 amps, but it should charge better at idle. I have an electronic external regulator already...

 

[Xenon]

Use a 60 amp three wire....
Power wire as normal ...
field wire as normal ...
and second field wire grounds to alternator case...

 

[Knebel]

Fantastic, are all 60amp higher idle output? Do I need to worry about frying the ammeter with a 60? Oh and are Powermasters any good/worth the cash?

 

[Xenon]

I have never fried an ampmeter or anything else by using the newer type
ALT on an older car....
1969 and older used the two wire and 1970 and up used the three wire...

As for the Powermasters,,, couldn't tell you one way or the other as have
not ever used them ....

 

[Knebel]

So basically just a standart 60amp alternator. I had replaced mine somewhat 2 years ago and I think that I got the 50amp version. Its just a little concerning when I start the car and it has 13v at the battery and then later on after driving for a while I never see more than 12.5volts. Thats just not right... maybe I add a wire from the alt stud to the battery to see if I just have a bad connection or so first.

Thank you for the advice tho, I'll be on the lookout for a newer 60amp!

 

[Big_John]

A couple thoughts.... First, make sure your voltmeter in the car is right. They really aren't all that accurate or reliable.

Second, with your EFI, electric fans and whatever else, you have a pretty big electrical draw. I would say that you aren't going to be happy with a 60 amp alternator.

Third, if it were me, I would consider changing to the 70 and up charging system. While you have an electronic regulator in place, there may be some benefits to the isolated field system. Along with that, I would start looking at the higher output alternators.

I have no input on the Powermaster line. Never used one.

I'm looking at doing the conversion to a 90 amp Dodge Dakota alternator for my 300. It's a cheaper alternative to the Powermasters (and others) and you can buy one off the shelf at a well stocked parts store rather than waiting a week for a replacement Powermaster.

Denso alternator upgrade - not the 60amp mini

 

[BJS racing]

The ammeter (which we do not suggest running anymore here at work) can handle up to about 65 amps before you have to start worrying about them anymore than normal. Make sure that the black and the red wire going into the bulkhead connector are clean and not starting to melt the plastic. I would unplug them and put some contact cleaner on them to get corrosion off of them then a little bit if dielectric grease to help in the long run.

The power master alternator are pretty good but they start at 100 amps for the most part and you will HAVE to bypass the ammeter or you WILL have problems. Maybe not right off the bat but that is more amperage than those systems are designed to work with. You will also have to add an additional charge wire from the alternator to the battery or it will burn up the factory charge wire.

 

[Knebel]

I have been thinking about adding a 4ga charge wire from alternator to battery, to begin with and see if that helps. With a 100 amp, could i add that wire but leave the ammeter connected or does it have to be rewired like in the madelectric instructions?

 

[BJS racing]

I have been thinking about adding a 4ga charge wire from alternator to battery, to begin with and see if that helps. With a 100 amp, could i add that wire but leave the ammeter connected or does it have to be rewired like in the madelectric instructions?

I would say that you should bypass it. It would help if you ran straight to the battery but I have seen way to many times an ammeter has caused some serious issues. The worst is when you do not have a car anymore.

 

[Ripinator]

. . . I'm looking at doing the conversion to a 90 amp Dodge Dakota alternator for my 300. It's a cheaper alternative to the Powermasters (and others) and you can buy one off the shelf at a well stocked parts store rather than waiting a week for a replacement Powermaster.

Denso alternator upgrade - not the 60amp mini

Sounds like a good plan, but I heard somewhere that you have to be careful with the higher output charging systems, etc., because the wiring in our early cars is just not up to carrying the higher loads.

But John, I'm sure you have already scoped out all the salient issues. . .

 

[Knebel]

Alrighty, here is an update on my charging system. I have a 60amp circuit breaker between the battery and the alternator/electronics. Never have any issues and never triggered, so I assume, that the alternator never maxed out over 60amps.

Now, I went ahead and bought 7ft 10ga wire (would have prefered 8ga but 10 was all they had) and formed a direct connection between alternator output and battery. What should i say, hovers at 12.9v at idle and 13.3v above idle. Perfect. Takes load off the ammeter too, which now dosent move really all that much. Only thing I have noticed is, that the 10ga wire to the battery gets quite warm, id say hot. But comparable to my fanwire and my standard wires. Also, i put it in a sleeve and have it across the engine, so that could introduce heat too. I guess i will be on the lookout for some 4ga wire and a mega fuse and do that the right way! But for now, its charging fine.

 

[BJS racing]

Go to www.waytekwire.com and they should have everything you need. That is where I order most all of my supplies for my wiring jobs.

 

[65Fury440]

You might want to jump that wire up to 10 GA at least.
Edit, read your post wrong, need coffee.

 

[BJS racing]

You might want to jump that wire up to 10 GA at least.
Edit, read your post wrong, need coffee.
View attachment 86344

but if you use TXL wire that chart isn't completely accurate. TXL even SXL can carry more current than the standard PCV coated wire from a parts store.

 

[65Fury440]

It's amazing how much better everything works with a charging wire. Removing the ammeter was a great move for me, sounds like you're going to be happy with the new configuration.

 

[65Fury440]

but if you use TXL wire that chart isn't completely accurate. TXL even SXL can carry more current than the standard PCV coated wire from a parts store.

Wow no kidding. I'm learning by accident, thanks!
Wire Size Calculator

When doing automotive wiring it is important to use the proper wire in the proper place, and this also goes for the operating temps of wire plastic casings (insulation). You don't want to run common cheap wire in a hot engine compartment, so make sure that you know the temperature range of your application and the temperature rating of the wire you are using. We have found that the "big box" automotive parts stores sell GPT wire (General Purpose Wire) that we do not recommend for use in high temperature applications, such as under hood. You are unlikely to find GXL/TXL wire in a parts store. While shopping for wire, you may see wire with specs like -

• GPT wire (SAE J1128-GPT) - General Purpose Wire rated -40F to 176F (Generic wire found in most auto parts stores)
• GXL (SAE J1128-GXL) - Thin insulation, Automotive Cross-link Wire rated -49F to 257F
• TXL (SAE J1128-TXL) - Extra thin insulation, Automotive Cross-link Wire rated -49F to 257F

GXL, and TXL wires are oil, gas, acid and generally chemical proof. One other note about wire type is Teflon and Tefzel are generally very good wire but expensive. And always check the ratings. We have seen Teflon wires with a temp rating of 105C(221F) which is below the typical cross-linked as indicated above. If you are going to get Teflon or Tefzel wire, it will be silver plated conductors and expensive. Typical temperature range for Teflon is -60C to 200C (-76F to 392F) and Tefzel is -70C to 150C (-94 to 302F). Sometime you may see wire called PTFE, PTF for Teflon as well. A few sources exist for Teflon wires, aircraft supply, surplus sometimes, even a few racing places are starting to sell it. We don't because it's overkill for most of our customers and there are not enough customers to warrant getting into selling it.

The voltage drop value will vary depending on your application. We prefer using the 2% mark as a conservative value and to ensure delivering full potential to any needed electrical source. From what it looks like in many automotive applications a 5% or more voltage drop is more common.

 

[65Fury440]

So the question begs to be asked, what kind of charging wire does OP have, or for that matter, what do I have?

 

[BJS racing]

So the question begs to be asked, what kind of charging wire does OP have, or for that matter, what do I have?

• GPT wire (SAE J1128-GPT) - General Purpose Wire rated -40F to 176F (Generic wire found in most auto parts stores)
• That is what the OE used up until the late 90's. They then went up to SXL in most cars and trucks. What is in your car is the same stuff you would buy at the parts store. Painless (which I work for) uses TXL on all of their harnesses and you can buy it through waytek or through delcity.

 

[Knebel]

Man, awesome info here! I was just browsing that shop and they have a minimum order of 100ft.... thats 90 more than what I need lol. And yeah, its amazing how much better everything runs when charging properly. Im wondering, the standart charge wire looks like its a 12ga or so, going to the ammeter. But yeah, I need to put a better wire system together to make it more reliable.

 

[Knebel]

Just a little update. With my additional wire connected, I seem to be charging fine, I might upgrade to a higher output alt at a later time because when the fan kicks on, it has a hard time charging. Idk, I have a small low pressure pump, under 5amps, efi pump maybe 10amps and efi system under 10amps. The fan has a 30amp fuse, it might draw 25 or so.

So I am at at least 50amps at idle with my 60amp alternator.... now count ignition, lights and whatnot and the alterntor cant keep up. I think putting in a 140amp with a big effing wire to the battery would do a world of good