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Unread 07-23-2017, 09:48 AM   #1
928gene928
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Default Alternator Conversion

Really tired of my stock alternator not keeping my battery fully charged, and the low charging voltage. Don't drive the car every day, so I keep a trickel charger connected in the garage.

I see where folks have installed the 1988 Camero 105amp alternator, with excellent results. Looks like I'll be making the conversion very soon
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Unread 07-23-2017, 11:19 AM   #2
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What alternator do you have and what are the voltage measurements? The dash gauge is fairly useless unless the alternator is not working.
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Unread 07-23-2017, 12:26 PM   #3
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Default Alternator Conversion

Glen,
Awhile back I measured about 13V. Also have done all the ground clean-ups, and connections to the alternator and ignition circuit. Also made sure the belt wasn't slipping. Have notice that with air conditioning and accessories on things just get worse. Considered adjusting the internal regulator by changing a resistor as described by others, or getting a high output 928 alternator. Frankly the Porsche units are too expensive, compared to $80 from the local auto parts store, with a nice replacement guarantee.

Have also changed the battery a couple of times.

I see from research that many folks have had similar issues, so it's time for a change.

Based on what I have read on-line, the conversion is easy, and provides 105amps. I'll be at the parts store tomorrow.
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Unread 07-23-2017, 01:21 PM   #4
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Some guys complain about the alternator from their dash gauges. Those do all kinds of things like sag as the battery charges. It's just the resistance in the grounds making the meter think bad thoughts.

If it's giving 13.5V (or close) at the jump post when idling then the alternator is doing its job. Turn on the accessories for a test. The alternators are voltage-regulated so it only puts out the current needed to maintain the target voltage. Higher-rate alternators, in Amps, won't necessarily raise the system voltage.

(Translation: a bigger alternator may not solve your problems and you may still need that battery maintainer.)

As for Porsche, the Bosch units are better (IMHO) as they are easily rebuildable for brush and diode failures. Those come in a handy module that attaches from the outside. At least in the past, local parts stores offered Bosch "928" alternators that are really off Audi's but fit and work...except for that the shroud doesn't mount up.
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Unread 07-23-2017, 05:35 PM   #5
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Default Alternator Conversion

Glen,
Thanks for the advise. This is a story that has been going on for years, and based on what has been said about the results by others, it is an inexpensive experiment. I will keep my original unit as a spare. As usual, I have dozens of projects underway at all times, and should get this one done fairtly quickly.

Will let you know how it works out.
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Unread 07-24-2017, 09:44 AM   #6
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I hope you meant battery tender, not trickle charger.
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