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Alternator Not Enough (Upgrade recommendations)

The pulley is what came on the Powermaster. I never mentioned that I wanted a high amp alternator but I want one that will produce enough at idle to put me around 13.5 to 14.0 volts. Is an alternator rated at 75 amps producing the 75 at idle or at a predetermined rpm? Thanks for your input!!!!

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At least an 8 ga wire from the alt to the battery then to you're loads... I hate to imagine that running through the original wire harness and amp gauge....

See post #1

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There is an amperage adjustment screw on the driver side of the carb. Turn it in a little to make the alternator charge more...

On a more serious note, your 136 Amp alternator does not put out 136 amps UNLESS the load requires it. Have you ever looked at the regulator? Put the race blue 732 regulator on; it helped my car out.

I might have to give that regulator a try. Thanks! What I don't understand is how so many other B Body Mopar owners (Google it) that have experienced what I'm now experiencing with my low voltage at idle have found the solution with a Denso alternator and some rated as low as 60 amps. That seems like an easy solution but I want more detail as far as which one (part number) and mounting bracketry.
 
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I'll give you $10 for the Powermaster since it obviously doesn't work.
 
It might be getting weak. I bought it used.
 
If you fix the bulkhead plugs that are slightly melted, I bet most of your issues will go away. My best guess on the real problem.
 
If you fix the bulkhead plugs that are slightly melted, I bet most of your issues will go away. My best guess on the real problem.

I have a 10 gauge wire ran straight through the bulkhead connector to eliminate that possibility and all the underhood wiring is new as is all wiring and connectors that complete the charging circuit. This is a complete resto-mod on a 10 second full interior, full body street/strip car.
 
I run a 50 amp from O'Reilly with a lifetime guarantee and a Hayden electric fan, shows 14.4 all the time
 
Mad electrical is a good place to start... Before any electric install. Let alone troubleshooting....
 
I had this issue with the oem alt not charging at idle, fixed that issue when I upgraded to electronic ignition with a Tuff Stuff 100 amp alt black powder coated one wire. Works very well. I'm not running any much more than my electric 14" pusher fan on a relay so I stay at 14vdc at idle all day long. Summit sells them.

http://www.summitracing.com/parts/tff-8509resp/overview/
 
I had this issue with the oem alt not charging at idle, fixed that issue when I upgraded to electronic ignition with a Tuff Stuff 100 amp alt black powder coated one wire. Works very well. I'm not running any much more than my electric 14" pusher fan on a relay so I stay at 14vdc at idle all day long. Summit sells them.

http://www.summitracing.com/parts/tff-8509resp/overview/

Thanks bigman!!! I will look into that one.
 
I'm needing some help with the charging system on my 69 roadrunner 440 with electronic ignition conversion and electric fuel pump. I have already upgraded the wiring and did the ammeter bypass trick. I went from square back alternator to 75 amp Powermaster and at idle I'm still slowly discharging. I'm thinking that a Denso might be a better unit for my setup. Are any of you running a Denso and if so, what did it involve and which Denso are you using? Internally or externally regulated? Thank to all!!!

Are running a one wire Power Master? if you are no charging will take place until 1200-1500 RPM. That is the design of a sinlge wire. If your running traditional you have the Alternator wired wrong. Trtaditional will put ot a small amount of juice at ide, only a small amount like 7-8 amps.
 
Are running a one wire Power Master? if you are no charging will take place until 1200-1500 RPM. That is the design of a sinlge wire. If your running traditional you have the Alternator wired wrong. Trtaditional will put ot a small amount of juice at ide, only a small amount like 7-8 amps.

The Powermaster is a three wire. I have MP Electronic conversion ignition with the post 71 flat style regulator.
 
I have bought a Denso 210 0138. I will post results (good or bad) when I get it mounted in the next few weeks. Thanks to all!
 
I got the Denso 210 0138 - 120 amp installed tonight. It was much easier to mount than I had anticipated. I used the factory alternator brackets but the adjustment is all the way out and the belt is tight for now. I might need a belt that is a couple inches shorter in the near future. I had to use ring terminals for the two field terminals as opposed to the spade type connectors and I had to modify the plastic isolator that is around the output post on the Denso to allow clearance for the factory gang wire ring terminal and the added 8 gauge wire ring termianl that is routed to the starter relay. I bought the alternator that is claimed to be new ( it looks new) for $35.00 on E-bay because the output post had been shortend 1/2 inch which is ok because that modification was possibly needed to clear the head. The alternator charges at idle as claimed. I had everything powered up including the headlights on bright, (man are they bright) and the voltage is 14.25 at idle! I think the engine is more responsive due to the increased voltage! I haven't taken the car out yet for a long drive but for now I'm thinking this could be the best upgrade I've made to date.
 
I have now taken the car out on extended cruises with no issues. I highly recommend this upgrade if wiring has been upgraded as mentioned in my previous post within this thread. I love it!!!
 
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440 Mopar with Denso 210-0138 120 amp alternator that does a great job at idle.
 
View attachment 188826

This is the best pic I have.
WTF....
I Would start over with the wireing and the transmission cooler lines..... check out madd electrical on the web.... unless you have a trunk full 12" speakers and amps a 75 should be ideal. I'm going to run a 140 amp powermaster.... the car will use 50a max and the stereo has 90a and it won't use all of it so the alt will run cool.
 
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