For the past 4 or more years I have been using the Bosch adjustable voltage
regulator. I set the maximum voltage at 14.10 volts at the terminal of the
auxiliary battery. This turns out to be 14.12 +/- 0.02 volts at the main
battery.

As I have detailed before, I had my alternator rebuilt at one of the LA area
alternator jobbers. We combined the front section from a Diesel vanagon with
the maximum number of diodes that Bosch provided (think it is the diode plane
for a Porsche 928) and the back-end from a Porsche 944. this latter detail
was so that I could mount the air cover from the 944 over the back of the
alternator. This cover is then connected by flexible rubber tube to a fan
blower (the fuel injector cooling fan from the Audi 5000 Turbo) sitting just
ahead of the transmission. The entry to the blower is a flattened scoop
mounted at the base of the frame level to scoop cool air while moving.
Remember, the major source of failure of the alternator is the loss of diodes
due to excessive heat. The engine compartment in the rear of the vanagon is
one of the hottest such zones put together by a major manufacturer.

As I recall, the alternator was rated around 150 amps. Not sure, but it is
easily equal to the 130 quoted before. I slipped the tech a spare $20 as I
left and thought the money well spent.

The shrouded alternator idea was a tip I got from listmember Alistair Bell.
Haven't lost an alternator since, used to go through them every 18 months.
Maybe it was 6 years ago, can't remember, neurons going, going ...

Frank Grunthaner