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Upgrading Alternator to a 95 amp unit what do I need to do for the gauge?

Started by BigmanjbMOPAR, February 15, 2021, 09:37:01 AM

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BigmanjbMOPAR

Is there some resistor or something I need to put on the gauge in order to use a alternator higher than 60 amps?
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chargerdon

Hopefully, you are going to (or have done) the bypass whereby you run either an 10 gauge or for 95amp preferably an 8 gauge wire directly from the alternators power post to the starter relay.   If you don't you are inviting melting the wires going thru the bulkhead and yes, they could catch fire.      

If you have done this then the amp gauge will be completely useless as 90% of the power is flowing thru the bypass wire.   You can simply leave it in place recognizing that it is no longer accurate and i promise you wont see nothing even close to the 60 amp.   Or best choice then would be to replace the amp gauge with a volt gauge... 14 volt is 14 volt whether from a  45-55 amp alternator or a 95 amp alternator.     

GoodysGotaCuda

You should bypass the ammeter in the dash and the bulkhead connections.

Consider adding a voltmeter to monitor charge.
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2020 RAM 1500 - 5.7L

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moreparts

I'm running the 95 amp Powermaster.  I asked their tech directly about it and they said no need to change anything.  That 95 amps is at full rpm, and much less at idle.  A few other MoPaRers have told me they've been running these for years with no problems. The electronics just draw what they need.  My gauge stays pretty close to dead center at idle.  And we do have a fusible link too in our wiring harness..

Poolshark314

Quote from: moreparts on February 15, 2021, 10:43:15 AM
I'm running the 95 amp Powermaster.  I asked their tech directly about it and they said no need to change anything.  That 95 amps is at full rpm, and much less at idle.  A few other MoPaRers have told me they've been running these for years with no problems. The electronics just draw what they need.  My gauge stays pretty close to dead center at idle.  And we do have a fusible link too in our wiring harness..

Does the gauge ever move away from dead center? I would expect if you have the alternator bypass in place, that the gauge never really moves anymore because it is no longer getting the majority of current through it, and is no longer accurate.
1973 Barracuda
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RSI700VIPER

Quote from: moreparts on February 15, 2021, 10:43:15 AM
.  And we do have a fusible link too in our wiring harness..

Don't trust the fusible link to protect anything.  Virtually all bulkhead and dash wiring meltdowns are caused by the battery amp wire carrying high current into iffy 50 year old wire harnesses.  And virtually all of the meltdowns occur with the fusible link in place.   

chargerdon

Quote from: moreparts on February 15, 2021, 10:43:15 AM
I'm running the 95 amp Powermaster.  I asked their tech directly about it and they said no need to change anything.  That 95 amps is at full rpm, and much less at idle.  A few other MoPaRers have told me they've been running these for years with no problems. The electronics just draw what they need.  My gauge stays pretty close to dead center at idle.  And we do have a fusible link too in our wiring harness..

LOL...Look i don't know in what year Powermaster began making the 95 amp alternator, but, ill bet it was several years after 1974.   So, i doubt very much if the tech at Powermaster knows that mother Mopar used 12 gauge wire in the stock wiring harness thru the bulkhead.   12 gauge wire is only good for about 30 amps before overheating.   look it up if you don't believe me.   This site is full of info on how to do the amp gauge bypass...   and for good reasons !!!!!!!   12 gauge wire running thru the bulkhead is DANGEROUS !!!!!!!!!!!!! with the 45 amp stock alternator and suicide with a 95 amp !!!!!    True, most of the time with a fully charged battery the regulator will have the alternator only put out what is needed to run the car and keep the battery charged.   At night, the electronic ignition system, and headlights/tailights, interior lights,  radio and heater fan will require about 20 amps...    but..when you first start your engine, the starter draws a lot of amps, and the alternator has to replace the drain to keep the battery full.   During this 1/2 minute or so the alternator will easily with all accessories on put out about 2/3 of its rated capacity.   

Now, try this even with your current alternator.   Turn on your headlights and radio for an hour before starting your car, and then drive it down the road...ill bet your amp gauge will show at least 30+ for about 1/2 hr until battery is fully recharged.    Now go ahead...if you dare...   Put in the 95 amp alternator, let headlights and radio on for about an hour before starting your car, start it and now drive it down the road, and ill bet you show for about a half hour close to if not past the max mark on the amp gauge which is 60 amp...   that's if you actually can drive it until battery is fully charged without melting any wires and catching a fire !!!   

Be smart, a 10 gauge or better yet an 8 gauge wire will only cost you maybe $20 or so, and the bypass wire to the starter relay (with either a 60 amp in-line fuse or fusibile link is easy to install.   It bypasses the poor connections in the bulkhead, and passing all of the charging current along with the required auto draw thru the heavier cable !!!   


BigmanjbMOPAR

 I'll run a new wire over to the alt from the relay I did this in my b body. And I bypassed the amp guage just in case. I have the power master 1 wire so there is no need to use the old amp gauge. Was considering it but Its not worth the fire plus my son will be driving the car so even more reason.
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