High output alternator recommendations

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CluelessMopar

CluelessMopar

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I recently went the route of adding the Holley Sniper EFI, Hyperspark, & a in-tank fuel pump to my 1969 Dodge Dart w/ 360. I believe I'm at the point where my stock alternator is not producing enough amps to keep up with these new electrical components I've added (albeit I'm having a hard time finding the exact amp usage these systems are using via online). The car only registers about 11 volts charging on my volt gauge event when I'm at 4,000+ rpm. I'm starting to look into upgrading my 55 amp alternator to this 100 amp 1 wire alternator:

CHRYSLER Top Street Performance ES1013BK Top Street Performance Alternators | Summit Racing

Are there are other alternators I should consider? Is there a good reliable way to tell just how much my entire system is using in amps?

If I do upgrade my alternator, what do I need to do as far as wiring my volt gauge so the new alternator doesn't fry it?

Apologies for all the questions, but I'm sure I'm not the first person to be under powering their electrical components in their car :)

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You need to do the bulkhead/ ammeter bypass if you have not done so, or at least convert the wiring to mimick the so called "fleet police taxi" where the bulkhead connector is "partially" bypassed. You can look this up in some of the shop manuals from "about" 70-72 avail. for free download at MyMopar. Look up the 65 A optional alternator wring diagram for the B bodies
 
^^^^^........X2, wiring should be upgraded anytime You up demand, & give it what it needs. Just dumping in a high output alternator can burn-up the wiring even w/o everything running if the battery SOC is too low...& Mopars have the extra bulkhead/ammeter hazard.....research & do as suggested in post #4...
You can't burn-up the voltmeter, only if it overcharges, which can happen if there are poor connections. You should take the voltage close to the batt., fused wire at starter relay B+ post is accurate, it will give You an early heads-up over/under charge.
 
I upgraded to 60amp when I installed my Sniper. I’m assuming you don’t have electric fans, or any other high draw stuff? I did crackedbacks headlight relay kit, and his alt-batt charging wire. I hold 14.3-14.5 from idle on. Sniper only draws 2-3a, my fuel pump can take some though. May want to test the alt you got, ensure it’s putting out 55a
 
Backally said:
I upgraded to 60amp when I installed my Sniper. I’m assuming you don’t have electric fans, or any other high draw stuff? I did crackedbacks headlight relay kit, and his alt-batt charging wire. I hold 14.3-14.5 from idle on. Sniper only draws 2-3a, my fuel pump can take some though. May want to test the alt you got, ensure it’s putting out 55a
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Dummy question, but what's the best way to test the amp output of your alternator?
 
I cannot echo post #4 enough. The wiring should be upgraded FIRST!
 
CluelessMopar said:
Dummy question, but what's the best way to test the amp output of your alternator?
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You need a battery/ starter / load tester, otherwise known as a "carbon pile." The "simple" idea s that you get the thing warmed up and "normalized" then turn everything off in the car that you can, then load the battery until the system voltage comes down to a specified value, 13.2 or 13.5 if not otherwise specified, and read the ammeter on the tester. Then figure in any loads in the car such as pumps, cooling fans, etc that you could not otherwise shut off
 
Another method that's not as accurate, is to turn on all electrical components on high, and use a DC ammeter clamp to measure how much current is actually being drawn from the alternator under full load. A shade tree mechanic approach, but doable if you or your friends have an amp clamp.
 
..........Except with many alternators you may not have enough load on board to fully load the output.

Still another way is just watch the voltmeter.......with everything on "you can get" (start with the battery charged) set a nominal 13.5 for a minimum and see how low an RPM will still "run everything." That will give you a "redneck" view of how much headroom you have
 
What other elect accessories other than Sniper have been added that require a 100 amp alt? I think you have a charging problem, not necessarily the alt.
 
67Dart273 said:
You need a battery/ starter / load tester, otherwise known as a "carbon pile." The "simple" idea s that you get the thing warmed up and "normalized" then turn everything off in the car that you can, then load the battery until the system voltage comes down to a specified value, 13.2 or 13.5 if not otherwise specified, and read the ammeter on the tester. Then figure in any loads in the car such as pumps, cooling fans, etc that you could not otherwise shut off
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Something tells me you've been in the electronics field for a long time. Respect sent.
 
CluelessMopar said:
Dummy question, but what's the best way to test the amp output of your alternator?
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Remove the alternator and take it to one of the automotive retailers like Autozone, they do free alternator testing. I have a vehicle with fuel injection, electric radiator fan and when I ran the ac the volt meter in the vehicle would show the voltage slowly drop over time. I was going to upgrade the alternator but decided to have the one in the vehicle tested. Turns out that alternator was not putting out what it was rated at. I replaced that alternator with a new one, same rating as the original one and now with the ac and headlights and all the other accessories on it keeps up.
 
my68barracuda said:
Remove the alternator and take it to one of the automotive retailers like Autozone, they do free alternator testing. I have a vehicle with fuel injection, electric radiator fan and when I ran the ac the volt meter in the vehicle would show the voltage slowly drop over time. I was going to upgrade the alternator but decided to have the one in the vehicle tested. Turns out that alternator was not putting out what it was rated at. I replaced that alternator with a new one, same rating as the original one and now with the ac and headlights and all the other accessories on it keeps up.
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I don't know about "specifically" Autozone, but many parts store testers are not up to that task. Many cannot and do not actually load test the thing at full output, more of a "simulation.
 
67Dart273 said:
I don't know about "specifically" Autozone, but many parts store testers are not up to that task. Many cannot and do not actually load test the thing at full output, more of a "simulation.
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All I can say, as mentioned in the my post that it worked for me. And I recommended it to the original posted as it makes much sense to get a free analysis prior to blindly swapping a part out.
 
I run the ProFlo4 EFI, in tank 340lph Areomotive fuel pump, electric fan, and the mad bypass on my cars and both have no issues at idle holding 14V even with the headlights and A/C on. This voltage is verified by the dash gauge hooked at the fuse block and the ProFlo4 data which is sensed at the starter relay. Stock alternators. My bet is you have a wiring or alt issue.
 
67Dart273 said:
.........Except with many alternators you may not have enough load on board to fully load the output.
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s this because the battery provides some of the load/voltage/amperage?
 
One thing I did besides upgrading my alternator was definitely upgrading my battery. Even the high output alternators don't really put out high volts until you're at a little bit higher cruising RPM.. like on a hot day when I have the AC going and the electric fans on the motor going at a stop and the car is idling, there's no alternator that's going to keep all that stuff running at that low rpm. That's when you rely on a good battery until the RPMs come up and it can recharge...
 
mopar505 said:
s this because the battery provides some of the load/voltage/amperage?
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No, simply because you may have a larger alternator than the loads. Which "you hope" is the case. Even when these cars were first built (with alternators) in the early days, 37A units, back then everything in the car except the starter would not be more than the 37A.

Which is why you need some kind of load that you can quantify, IE measure
 
67Dart273 said:
No, simply because you may have a larger alternator than the loads. Which "you hope" is the case. Even when these cars were first built (with alternators) in the early days, 37A units, back then everything in the car except the starter would not be more than the 37A.

Which is why you need some kind of load that you can quantify, IE measure
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Understood.. That being said, if the OP has two fans with running amperage of 20 per unit would he see 40 at the battery wire on alternator with Dc amp clamp? Just trying to wrap head around this.
 
Yes, should. When a system is properly operating (and being old, why I like ammeters) when "running down the road" so to say, loads on the system, lights, heater, fans, anything else--should keep the ammeter AT ZERO (centered) IE the battery is charged, "up and normal" and is doing "nothing." No current entering or leaving the battery, so whatever loads are being fed by the alternator

Basically an ammeter IS a "balance" indicator for the battery. You put ONLY the battery (except the starter) on one side of the ammeter, and everything else---all loads and the alternator---on the other side.
 
67Dart273 said:
I don't know about "specifically" Autozone, but many parts store testers are not up to that task. Many cannot and do not actually load test the thing at full output, more of a "simulation.
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Correct, they simply indicate any excess resistance/shorts thru the brushes-slip rings-rotor windings, & check voltage ripple to ensure all the diodes are shutting the gates under load. I'm not sure any of them "full field" them with enough load to check max output accurately.
 


reset and clamp onto a running cars battery lead to see what its drawing.
 
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