[SupraFiend]

I rebuilt an alternator that had died once and it started doing that. I had actually replaced the regulator in my old alternator. I think I fried it when soldering it on. Ended up getting a refurinshed one and it worked. It did exactly what your is doing too, voltage goes up with the revs. Its possible your new alternator is bad. Is it a refurnished unit too? You have to be careful with those, some companies just change what they think has stopped working on them then resell it. For instance that one I got the bearings went within a year. Luckily it was still under warrentee.

 

[SupraFiend]

your parts car have one that works by chance? Maybe try a good one before you shell out for a new one.

 

[SupraFiend]

you can replace the regulators on the early mk2 alternators, but I don't think you can on the later ones, I don't remember why exactly. Napa was the only company around that sold a regulator for my old 82.