Alternator upgrade

Chris,
Sorry about the delayed response. Unfortunately this work gets done in the margins. No the bolt holes are not the same. The newer alternator definitely has larger bolt holes.
I am figuring I will need to get the old one rebuilt and I have a shop that is willing to try. Are they going to have issues finding parts too?
Best, Greg
 
I hope this helps others:
The Bosch AL655N was a great replacement for the OEM alternator on my '72 3.0cs in regards to fitment and alignment. One of the threaded bolt holes had to be drilled out to accept the slightly bigger factory mounting bolt and took less than a minute. The pulley had to be swapped over. We now have 14 volts at idle with AC Condensor Fan, Lights and Wipers on as opposed to 12 volts and the lights going dim. All with the comfort of a new "made in USA" Bosch alternator. We also used this plug for a cleaner install in regards to the D+ battery light wire.

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if you have to change things, i highly recommend the change to the newer style adjusting rod from the e30.
i used the 80a AL-46x with the e12 fan (12311350199) and the e12 pulley (12311362465), the bracket 12311274747, with the toothed nut 12317677914
 
I have what I suspect is an internally regulated alternator that I may have cockroached from a '81 528i that I parted out long ago, mainly for the 5speed trans. It is visually identical to the newer version in post #20. It has a reman sticker on it, over the (unreadable) original Bosch sticker. How can I determine its original identity and amp rating?

Can someone confirm that an internally regulated alternator needs the only a wiring connections are red to D+ via the ignition switch (and battery positive) , a ground from the alternator body to engine block, and wire from alternator D+ to the voltage regulator?
 
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