Keep in mind the forward voltage drop of the diode will also increase the
alternator output. You would be much better off to repair the wiring to
reduce the voltage drop then to compensate by increasing the output of the
alternator. Keep the following points in mind:

The alternator has internal resistance. This is what really limits the
current it can produce.
At full load this resistance means that it is creating as much heat as the
power it is delivering. Voltage X current = watts.
So if you increase the voltage by 10%, at a given current you will be
producing 10% more heat. You also need more HP going into it.

Most of the voltage drop to the battery can be eliminated just by upgrading
the wire from the alternator to the starter battery post. Another wire from
the battery to the fuse box will do wonders.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
David Beierl
Sent: Sunday, July 18, 2010 7:31 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Alternator output

At 05:04 PM 7/18/2010 Sunday, Alistair Bell wrote:
>We discussed this a month or so ago, David B. talking about adjusting
>alt. output.

To be strictly precise I was talking about moving the alternator
sensing lead to the battery instead internal to the alternator.  I
haven't installed the one I modified yet, I still have to add a diode
for insurance.  And of course run a wire to the battery.

Yrs,
d