alternators ?

[davek]

So my Bee has an old alternator maybe pushes 50 amps, Can I put a newer one on that pushes 95 amps and have no problems? Do I have to change any wires? wanted to upgrade so I thought I would ask. Some thing like this from Summit. https://www.summitracing.com/parts/pwm-75091/make/dodge/model/coronet/year/1970

 

[zyzzyx]

I've seen alot of guys put the Denso alternators on with either 60 or 100A?
Seems like a great idea to me.

 

[Darter6]

True, But keep in mind that these cars had 38 to a max of 60 amps when new.
Many do the amp meter by-pass when going to a 100 amp alt.
The bulk head connector overheats at the firewall and can do serious damage.
Not saying that it happens to all but I've seen it happen.

 

[zyzzyx]

I grabbed this screen shot from a Google search and I think it was originally on our site.
Very interesting.

 

[zyzzyx]

One guy explained how he wired the alternator directly to the battery terminal, put the headlights
on a relay, and this took all of the load off of the Bulkhead connector? I dunnow, sounds good to me?

 

[R413]

Why do you need more amps? More is not automatically better as stated above.

 

[dadsbee]

You gonna run a mobile disco service out of the trunk Dave???.. or an electric cabin heater...

 

[threewood]

I just swapped my old one wire alternator for a Denso alternator and it was a simple and very worthwhile upgrade. No lights dimming at idle. Puts out 14.3v at all times. It is internally regulated so you can bypass the old VR.

I had already done the MAD upgrade and installed relays for the lights. Anything to take the load off of the bulkhead connector and old switches is worth it.

Wiring was simple. I had to run an alt sense wire directly to battery. The other two alt wires were reused.

Original brackets are perfect. I only needed two 5/8" spacers.

 

[SDCoronet]

I’ve read lots and lots of posts regarding this issue because I will probably have to do the upgrade soon. I plan to do the alternator upgrade, in addition to the parallel wiring mod.

The problem is that our old alternators do not put out enough current at idle.

Read nachos’ posts here.

http://www.dodgecharger.com/forum/index.php/topic,33574.0/all.html

 

[Nacho-RT74]

So my Bee has an old alternator maybe pushes 50 amps, Can I put a newer one on that pushes 95 amps and have no problems?

which it means the stock one barelly puts out 25-30 at iddle being optimistic. And I guess even less if got the big diameter pulley which is the used on those years. Depending on manufacturer a 95 amps should be on 55-65 amps rate at iddle, tipically with the smaller pulley which is an ideal status. Don't be affraid but take care of bulkhead.

having 95 amps capacitity doesn't mean will source 95 amps... or 55/65 at iddle will source that. Simply it means will be able to source that IF the car request that. Still with an alt able to cource 55/65 amps at iddle but the car just needs 35, the alt will source just those 35. And very important, with a very constant voltage rate.

BTW, amperes are not pushed in by the source but pulled out from the source!

 

[davek]

You gonna run a mobile disco service out of the trunk Dave???.. or an electric cabin heater...

Just ordered this for the Bee

 

[davek]

When I get bored I think upgrading,I forget these cars have worked for 50 years so why change things if its not broke .

 

[Nacho-RT74]

the alt upgrade can be now, the wiring upgrade can be later. The car will keep sucking the same load, but with a better alt, the charging system will be less stressed since wthe batt will be safe from being sucked out and charging back again, so the full charging system will be playing with less load on the system. Trust me

Lets say your car sucks out 35 amps on the basic equipment, but at iddle the alt gives you 28 amps. that will get you a 7-10 amps load being sucked from the batt because the car will be requiring the same 35 amps no matter who is able to give those. As soon you gives RPMs, the alt will be able to supply those 35 amps AND maybe 10 amps more to recharge the batt. That will be 45 amps running throught the bulkhead on alt wire for quite some time. It will be playing with that charge-discharge process allways according with RPMs, and a back and forth ammeter reading

Now, imagine you get an alt able to provide those 35 amps the car needs. It means the batt will be never requested to get the missed load, so the bulkhead will be never forced to hold 45 amps to feed the car AND charge the batt back, but just the 35 amps to the main splice at alt wire. So the bulkhead is even safer with a better alt.

EXCEPT after crank up the engine of course, because the batt will request what it lost while cranking. There is no way to sway that but it usually takes maybe 5 to 10 minutes depending on alt and how much did you crank. That's the most important moment to get the wiring upgrade. But maybe just one wire, the alt wire up to ammeter on a parallel path could be even enough

 

[70chall440]

There are really 2 issues at play here; first is the less than adequate wiring system and the second is the lack of amperage available via the stock alternator. When the cars were new and all of the connections were bright and shiny, the alternator probably did ok but I doubt it because even back in the day the lights would dim at idle, at least the cars I had that were 4-5 years old did.

Because the wiring in many of these cars is aged and the HL circuit is lacking, it causes issues trying to push enough power to them while at idle and not get the circuit hot, therefore it is HIGHLY advisable to run your headlights off of a relay which then takes all of the load off the switch which allows the HLs to stay bright. Also, many people decide to add Halogen or even LED headlights which tend to draw more power (halogen specifically) which then means the stock alternator cannot keep the battery charged thus the need for a higher output unit.

As for the alternator itself, they were not bad but barely adequate for what they were put in, however they did work somewhat when new (until you added anything electrical that had any significant draw such as a big stereo into the car). So, with this there are some options; the stock alternator was usually around 60A, Mopar did make a 90A and I believe even a slight larger one for emergency vehicles. Therefore it is possible to up the stock alternator to a point which bolts right in. Also, there are aftermarket alternator from like Power Master that emulates the stock profile and generally bolts right up (I believe).

The other option is to retrofit a Denso alternator which can be had in a variety of sizes but I prefer the 120A in my builds. Installing it is not super difficult, there are companies that make brackets but I have found they can really be dependent on the specific pullies being used. One of the primary upsides of using a Denso is that you can get one from any auto parts store relatively cheaply. They do not really require a lot of new wiring but they do require that the amp meter be bypassed.

Lastly, regardless of what you do, probably the one biggest positive thing you can do for your car is clean all of the grounds, install more grounds (cannot have too many).

 

[davek]

I dont drive the car at night and no stereo , I see some people put a wire from alt to starter relay,does that take part of the load off the bulkhead?

 

[70chall440]

I dont drive the car at night and no stereo , I see some people put a wire from alt to starter relay,does that take part of the load off the bulkhead?

No, when people talk about taking the load off the bulk head they are referring to the amp gauge/meter bypass. The problem is that in the factory configuration the charge wire from the alt goes to the amp gauge and thus powers everything and eventually routes back to the battery. This puts a lot of load/current on the Packard 56 connectors in the bulkhead which when clean and new isn't a big deal, however with time and corrosion it begins to cause issues due to heat build up (there and in some vehicles with the ignition switch on the column on the steering column connection).

I run my alternators directly to my battery and run relays on all my high draw items such as the headlights, electric fans, etc.

 

[multimopes]

I have been running that exact Power Master alternator for over 5 years without mods. Note- I Don't have an ammeter anymore, or bulkhead connection to worry about. Voltmeter wires make a home run to the alt. I got it because the diodes in my old alt intermittently went bad. Also I have dual electric fans that pull a lot of juice, at idle with both fans on, voltage drops to 11 which sux. This is a nice unit but lacks the ability to supply enough voltage at idle. If I wasn't in a hurry, I would have gotten an internally regulated unit as discussed above!

 

[RJRENTON]

which it means the stock one barelly puts out 25-30 at iddle being optimistic. And I guess even less if got the big diameter pulley which is the used on those years. Depending on manufacturer a 95 amps should be on 55-65 amps rate at iddle, tipically with the smaller pulley which is an ideal status. Don't be affraid but take care of bulkhead.

having 95 amps capacitity doesn't mean will source 95 amps... or 55/65 at iddle will source that. Simply it means will be able to source that IF the car request that. Still with an alt able to cource 55/65 amps at iddle but the car just needs 35, the alt will source just those 35. And very important, with a very constant voltage rate.

BTW, amperes are not pushed in by the source but pulled out from the source!

Once again, your premise, or understanding (?), or guess, is incorrect. Not sure where you learned electrical engineering principles but, perhaps, you should consider reviewing the basics, such as Ohm's Law or Kirchoffs nodal analysis of electric circuits.
Kirchhoff's current law states that current flowing into a node (or a junction) must be equal to current flowing out of it. This is a consequence of charge conservation.
Kirchhoff's voltage law states that the algebraic sum of the potential differences in any loop must be equal to zero as: ΣV = 0.
These laws are fundamental to understanding the how and why an electrical system functions, not on your assumed (incorrectly) suppositions. If you would like to discuss further, just PM me.
BOB RENTON

 

[383man]

Like Nacho said you could put a 500 amp alt on your car and as long as you have not changed anything electrical on the car the alt will only put out what the car demands because the voltage reg will cut the amps back as soon as desired voltage is reached.
I can tell you I put a 100 amp alt on my 63 and I have only added an electric back-up fan to it. Now my stock alt was about 35 to 40 amps and I had no battery problems at all. But when you look at how to test older alt's they tell you check output at 1500 to 2000 rpm as thats where they need to be for full output. So with my old alt when I came to an idle in gear at night with my headlties and electric fan on my volts would drop from 14.2 to about 12.8. As soon as I touched the gas my volts went right back to 14.2. Now with my new 100 amp alt my volts stays at 14.2 at idle in gear with everything on since it will put out 65 or more amps at idle. But its not putting out any more then the old alt did when on the gas because thats all my electrical system demands. If I add more electrical things to the car then I may need to upgrade wires if I make the alt put out more then before. It never hurts to upgrade any wiring but if you simply bolt a larger alt on and the old one put out enough to supply the car the larger alt will only put the same out that the car demands. Ron