Re: [DML] Soft alternator?

["Walter" <Whalt@xxxx>]

Kevin,

A low voltage situation at idle is normal in the DeLorean especially with
accessories on like headlights and a/c. I have one of John Hervey's 140amp
alternators in my D now, and it is a vast improvement; however, at idle the
system voltage will be less than 12 volts with the a/c on. A slight
increase in RPM will bring the voltage up to a reasonable level. You might
try using a smaller pulley on the alternator so that it will turn faster,
but there are limits to how small you can go.

I have seen larger pulleys in aftermarket catalogues to slow the alternators
down for racing purposes. (The slower the alternator runs, the less
horsepower it takes away from the car). I would like to do this for the
DeLorean, but... BUT... then you get too low a voltage at idle. I suggested
designing a two speed alternator a while back, but it quickly got moderated
off the list. Someone suggested using two alternators -- one that runs at
high RPMs at idle and then kicks off at higher RPMs. This might be done
with an a/c compressor clutch, but I have more important projects to work
on. I suggest trying a smaller pulley or a better alternator. I already
have a better alternator with a somewhat smaller pulley, and it could be
better. Although I believe that it is the best out there unless John's
newer 150amp alternator is any better.

Ideally, someone needs to come up with an alternator that will put out a lot
of power at low RPMs yet be able to handle spinning at very fast RPMs
without flying apart or taking too much horsepower from the engine. Some
guys will say that any alternator should handle excessive RPMs and that it
won't take away from the horsepower too much. If you are one of these guys,
then put the smallest pulley you can find on there.

Food for thought,
Walt Tampa, FL