DeTomaso Mailing List: July 2001, Message #57

Go to any airport.  Look at the real airplanes, those with piston engines
and propellers.  Find one with an alternator driven by a belt, not gear
driven.  Ten bucks says it's a Ford alternator that looks just like the one
that came on the Pantera, but turning backwards.  Same regulator too, if you
can find it.

Guy D.

(yes, I know some of them at the airport are 24V, that's not the point here)

----- Original Message -----
From: Kenny Hall <Kenny.Hall@servatron.com>
To: Multiple recipients of list <detomaso@realbig.com>
Sent: Thursday, June 28, 2001 3:17 PM
Subject: Re: Alternator / Dreams come true update


Correct me if I am wrong, but...

All, yes all, alternators I have seen on automobiles (pickups, trucks) turn
the same direction.  They are all driven on the inside of the belt wrapped
around the crank pulley, therefore they rotate in the same direction as the
crank.

The serpentine belt systems I have witnessed (an mind you, I have not seen
them all) only drive the water pump and some idler pulleys in a "reverse
rotation".  All other accessories are turning in the same direction as the
crank (smog pumps, alternators, A/C units, power steering, hydra boost
pumps, etc).

I believe an alternator works better turning one direction compared to the
other (I am not an electrical engineer, and who is this Ohm guy?), but all
the ones I know turn the same direction (check the fan blades).

As for driving the alternator off the cam (which turns at ½ the speed of the
crank), is the alternator positioned in a "stock" arrangement, i.e. the
pulley end faces forward? If the answer is yes, then it is turning the same
direction as the crank, and any old alternator will work.  You will need to
adjust pulley size to pick up the speed lost due to the "slower" camshaft.

Kenny

>>> "Nolan Scheid" <nolan@clipper.net> 06/28/01 02:47PM >>>
Jack and others,
That is an interesting question about the alternator turning the wrong
direction.
On my new aluminum motor, the dry sump is driven directly from the cam. I
have found that Fisher sells the parts to add a harmonic balancer and cog
drive for the wet sump while keeping the crank driven KSE water pump.
http://www.fisherconcepts.com/
That would leave me with an opening from the cam to drive the alternator. Is
there an alternator that would turn the correct direction when flipped
around for direct drive? Is there an alternator that would produce good
current at the slower speeds? Another option would be to use the cog drive
for the alternator and go to a wet sump. Any suggestions?

The last package of engine parts just arrived for my dream stroker. It is
the Hilborn injection with 2.5" butterflies. On top of the 8 giant Velocity
stacks are tall K&N filters. This is really cool, now the best use of my
rear view mirror will be to watch the throttle linkage rotate the
butterflies .
  :)
In the end the complete motor was as advertised and other than a bit of race
dirt it appears new. Now I need to form a plan for which parts I will need
to get the motor ready for a street car.
Diablos watch out.

Nolan





----- Original Message -----
From: <JDeRyke@aol.com>
To: "Multiple recipients of list" <detomaso@realbig.com>
Sent: Thursday, June 28, 2001 10:41 AM
Subject: Re: Alternator


> All the late style alternators I've seen are small in diameter but just as
> long as a stock one. So you gain nothing in terms of positioning it
further
> back from the engine cover, to allow the passenger seat to set further
back
> (the flat-firewall thing). And most of the unit's weight is in the rotor,
so
> the little ones (of equivalent output) are not significantly lighter than
a
> stocker. I see little advantage and lots of extra cost. Plus, if it was
> originally a serpentine belt drive, the vee-belt pulley must be
retrofitted,
> or the whole engine converted. A vee belt will spin the alternator
backwards
> from its design direction; the field excitation brush is sometimes offset
in
> the preferred direction, making for a reliability question. Good luck- J
> DeRyke
>
>