Which Alternator Do I Need???

[westie47]

OUT OF CURIOSITY, WHY do you think you need a high current alternators for a relatively stock application? Contrary to others comments, NOTHING will be gained by using a 110 amp alternator in lieu of the stock or origional capacity alternator. As I've noted previously in a similar thread on this forum, it is NOT the total connected load but the PERCENTAGE of load connected that requires power. The term is called the diversity factor. The nation's electrical utility grid relies on this factor 24 hrs day / 7 days week. IF the grid were required to supply 100% of the total connected load, the grid would need to be several orders of magnititude larger, which is not feasible or affordable. USUALLY only 15% - 25% of the total required power is needed. The same philosophy was adopted by the MOPAR engineers when the vehicle's systems were designed. Therefore, the balance of power needed by the vehicle for operation, is supplied by the battery, on a TEMPORARY basis.....this is perfectly acceptable. And the power withdrawn or consumed (not sucked out as vocalized by others..get the terminology correct), will be replaced when the load is reduced and normal operating conditions resume. The world will not come to an end if the battery supplies a percentage of power required for operation.....what works for the utilities will also be applicable to vehicle operation.....the diversity factor. I'm sure that this fact conflicts with your next door neighbor's, cousin's husband's sister-in-law's nephew's best buddy's friend thinks about the subject. I'm sure that others will disagree the premise.
BOB RENTON

Thanks, I really struggle with understanding all things electrical, which is why I asked. I was looking at ordering an alternator from Summit and there's just too many to choose from, which causes me the confusion.

 

[westie47]

I don't have answers, but questions?
Are you using the original crank / waterpump pullets and alternator brackets?
If so, then the stock style alternator needs a pulley with a stock offset to have the belts align.
I was chatting with another member who was changing from a dual v-belt to single v-belt, and the pulleys are not aligned.
If the crank damper is aftermarket, some don't have the stock thickness which also moves the pulley / belt alignment off.

Most of the aftermarket replacement alternators like Power master have both field terminal connections that can be connected to so they will work with the older 1970 and earlier style voltage regulator, or the 1971 and newer style voltage regulator.
I think original style was the round back alternator? I never used a Power master replacement, but their round back version would look period correct. Seems they are built to the same specs as the square back alternators?
Looks like the 7018 is a single pulley version and 7019 is a dual pully version?

The engine is set up completely to look stock. The wiring harness is a stock repro but modified for electronic ignition conversion. Stock water pump pulleys and brackets. I'm running the 69 style voltage regulator.

 

[Nacho-RT74]

Making rude maths about why increase the alt capacity leaving the batt out of the game as much as posible ( more than factory did )

With stock alt let's say the total of your car loads requirement is 30 amps at certain stage ( WHICH IT HAPPENS turning in couple of accesories, lights, sure not just with ign system ) and you have 45 amps stock alt. With the big pulley they came out it could be providing barelly 20 amps while iddling. This means the batt will provide 10 amps... the discharge reading will show this load being sourced by the batt.

Now, you rev up the engine... alt is now able to provide its full output, 45 amps. Battery will claim the lost load and will get charge reading. It means THROUGHT THE BLACK WIRE AT BULKHEAD, will be running 45 amps, 30 to feed the car request which is constant and just reachs the main splice ( before the amm ) and the battery sucking the extra 10-15 amps ( amm shows that charge getting back to batt ), on a packard terminal which barelly is able to hold 30 or 35 amps...

After all these years of regular use, wonder why 75% of Mopars get their bulkhead burnt or melt, along with the related wiring. Black cavity first.

Now let's add more and think on the bad use and abuse... three stages:

1. Accesories added into the batt side. WRONG. More load being claimed by the batt side which IS NOT THE BATT, but amm with read it as a Charge.

2. Installing bigger batts with stock alts. WRONG. New batt will takes more time and load to finally get recharged and stop its load claim.

3. Points 1 and 2 together.

Now you can see why ammeters began to fail and Red wire at bulkhead provision also got melted.

You will see on bulkhead connections after this melting procedure along these years Black wire is considerably WORST than Red. That's the reason. You allways get MORE load running throught the black wire than the red wire.

And this is without think on dust, grease, copper degradation...

Conclusion... save the batt from being sucked constantly and you will be "turning off" that huge extra accesory running throught the charging system unnecessarily. Is not bad get more capacity batts, but the same the batt capacity is increased the alt needs the same.

Then, run a stronger wiring system on the charging circuit is seriously advised. I run a parallel wire to the stock throught the firewall up to the amm. Some ppl preffer despite the stock wire and just run a new wire up to the amm. I have my prefferences why still keep the stock wire in working order which can explain later. But STILL with the alt upgrade, down a stock car, the factory setup throught the bulkhead will survive better and longer than with the stock alt, just because you turned off the batt as a sucker accesory getting the main source ( the alt ) able to provide all the juice.

Sure if you want to get rid off the full load ammeter and link batt and alt together this is not a problem anymore, but keeping stock system working as intended, this is the way to make it.

 

[Dave6T4]

What do you think, Westie? Less confused, or more confused? Sometimes TMI.

 

[Hemirunner]

While we’re on the subject of electrons, shall we start the Ammeter discussion?

 

[Nacho-RT74]

What do you think, Westie? Less confused, or more confused? Sometimes TMI.

 

[Nacho-RT74]

While we’re on the subject of electrons, shall we start the Ammeter discussion?

Several threads about it. If that theme floats on I will just post links to those… and mostly sure if @72RoadrunnerGTX reads this, will chime in with the same procedure, posting links. I think this has been explained clear and long enough on them, still with squared heads being disagree LOL

 

[RJRENTON]

Several threads about it. If that theme floats on I will just post links to those… and mostly sure if @72RoadrunnerGTX reads this, will chime in with the same procedure, posting links. I think this has been explained clear and long enough on them, still with squared heads being disagree LOL

Including your normal, baseless diatribe, continuing adinfinitum, about issues discussed several orders of magnitude previously, without any substantiation (calculations)......BTW....."iddling" means nothing....and, I prefer "obtuse" rather than square as a definition......
BOB RENTON

 

[Nacho-RT74]

It was not for you but in general for the crowd not agreed about keeping the amm and what its readings mean… but if you bited it as personal calification maybe there is a reason for that. I have not offended anyone, yet at least.

But as expected…

 

[Hemirunner]

I have a used Tuff Stuff 7509RDSP if anyone is looking for a deal. I went to a serpentine setup with a GM one wire setup.

 

[westie47]

Oh yeah.....clear as mud!!!! *****walks out into garage, rips all wiring out and sits and cries...****

 

[451Mopar]

This is what I would do:

Stock look and fit, PowerMaster 7018, about $150
Catalog Link, Page 103:
http://www.powermastermotorsports.com/catalog.html#
Instruction Sheet:
http://www.powermastermotorsports.com/094__Chrysler_Alternators.pdf

 

[Nacho-RT74]

I have a used Tuff Stuff 7509RDSP if anyone is looking for a deal. I went to a serpentine setup with a GM one wire setup.

I can't find that alt PN on the tuffstuff website. Just as a case part replacement. All alts posted there are 8xxx or 9xxx

 

[Hemirunner]

I can't find that alt PN on the tuffstuff website. Just as a case part replacement. All alts posted there are 8xxx or 9xxx

It’s probably not a current offering anymore. It was purchased years ago and been off the car for several years. It’s a chrome plated square back IIRC.

 

[Nacho-RT74]

Yes I saw it at Summit, but not at TuffStuff. Weird.

 

[383man]

I use a Power Master Mopar style alt on my 63 Sport Fury. Its a square back 100 amp style and it fits perfect with all the stock parts. Now mine was an internal regulator but I changed it to an external since it had problems with the internal reg. The only thing added to my car is an electric fan and a Holley electric fuel pump. But one thing to remember is if you leave your car stock and put a 100 amp alt on as I did the alt will never put out anywhere near 100 amps if the car dont demand it as it will only put out what the car needs. You may need maybe 35 to 40 amps at the most so the voltage regulator will only let the alt supply the car and keep the battery up and thats it. The only difference I like with the 100 amp alt is it puts out up to 65 amps at idle. So at night with all my lights on and the electric fan on when in gear at idle the voltage stays at 14.2 even at idle. The stock 40 amp alt would drop to 13.5 or so at night in gear at idle with everything on but as soon as I hit the gas it came back to 14.2 and had no battery problems. I just like it keeping the voltage at the regulators setting even at idle with the loads on.
If I were you and your car is basically stock I would look for a Mopar alt around 60 amps and you will be happy and fine. You also need to know which regulator you want to use as most upgrade to the dual field electronic reg unless you want to keep the stock mechanical reg look. Ron