Please help me understand the difference between these parts
 

I'm new to air-cooled 911s (actually, to 911s in general -- I've owned a 981 Cayman and a 958.2 Cayenne for some time, but recently acquired an '83 911 SC) and I am trying to understand the difference between these two alternators:

This one is labeled "Genuine Porsche" - and - careful inspection of the second photo appears to show the marque "Valeo" on the rear cover.

This one is clearly labeled Valeo (as well as "OEM"), and as you can see there is a very large difference in price.

Can you please help me understand the difference(s) here? I don't know much (yet) about the history of these cars, but the shop with which I am working tells me that the Valeo alternator (for which they are quoting me the full list price of the first linked example, i.e. $1543.51) is the OEM option at this time, because "Porsche doesn't make those alternators anymore."

Thanks in advance.

They both do the same thing. I use Valeo if I can get one for a particular application. They're new and way better quality than a Bosch rebuilt.

The first one comes with that special Porsche tax, even though Porsche had nothing to do with the actual part other than look up a vendor list and make a selection.

Some parts that are sold by Porsche are identical to what you buy at other suppliers other than the Porsche box.

For what's worth, I installed a Valeo alternator on my 3.2 over 20 years ago and have had zero issues.

Yea, just get the new Valero. Best opinion.

Going back over this post again allows me to reemphasize that Porsche didn't make alternators - maybe for their race cars, but not for our daily drivers. Paris-Rhone (or Valeo), or Marchal, Bosch, ya, but not Porsche.

So, there is no "Porsche doesn't make those alternators anymore" in this case. This is a ruse to charge you for something that isn't and never was true.

This is not a shop you should be doing business with.

Back in 1996 or so, I had to have my factory original alternator rebuilt locally by a guy that did a great job. 29 year later, it started rumbling, and it was the bearings going bad. I tried to find a local rebuilder but they are really hard to find now days. I found a guy that had grown up in that business. He rebuilt it, but at installation, I had an alternator light. So I broke down and bought a new Valeo, and it works great. The old alternator struggled to charge when hot, but after 100,000+ miles it was tired.

The guy that rebuilt my old old one went out of business a few days after I had mine done. I am not in hurry, but I want the old one rebuilt, and have it on the shelf for the next time I need one.

Do yourself a favor and go to Rock Auto and buy it from there. No core charge and still save yourself over $250.

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