RE>bypassing alternator at WOT

["Chao, Harvey" <harvey.chao@xxxxxxxx>]

Regarding this thread - bypassing the alternator can reduce/eliminate power
diverted to the alternator and make it available to the drivetrain- yes, BUT
- - it would be of any value ONLY during times that the alternator is
generating any significant amount of power.

Consider - once the car has started and the alternator has recharged the
power withdrawn from the battery to start the car (generally only a few
moments) the output of the alternator is only enough to carry the electrical
load at any given instant - ignition, fuel injection, lights, radio - - - if
the load is minimal, so is the horsepower consumed by the alternator.

Consider:  one horsepower is defined as something close to 750 watts.  (That
is a theoretical conversion factor - but nothing is theoretical, there are
always losses and inefficiencies).  In practical term, lets say a 50%
efficiency in conversion (I'd expect a little better, maybe 60-70% ??) so
750 watts will consume 2 hp.  750 watts/13.4 volts = 56 amps.

You can run a LOT of stuff for 56 amps and only give up 2 HP.  Even my low
output 528e generates a max output of 120 HP.  2/120 =1.67%  !!!  Hardly
seems worth the effort, not to say the cost!  

Sounds more and more like e-ram to me  :-)

Regards

Harvey

"I live with fear, death, and evil...but sometimes I turn it off and
use a Mac. "  Author Unknown

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