It would only be feasible with a blower that was mounted ahead of the
throttle blades, like a Paxton or Vortech, and even then I would think that
you would need to include a valve of sorts to bypass the blower when the
clutch is disengaged. The tolerances on a Roots type blower are very close
for it to do its job properly. I cannot see much air getting past the
blades if they were stationary.
Speaking of disengaging clutches, this is kinda how turbochargers work. At
low rpms and throttle openings the impeller is basically freewheeling.
Imagine how a torque converter works and the turbo uses nearly the same
principal. A moving fluid (exhaust) is used to turn a fan. This exhaust
fan in a turbo then turns another fan (in the intake pipe) ahead of the
throttle blades that pressurizes the intake air. As you add more intake
air you get more exhaust air you get more intake air (it builds on itself)
until the engine restrictions begin to slow the process down. This is why
turbos have the "turbo lag", it is because the turbo unit is sized larger
to move a relatively larger amount of air, and it needs more engine rpm to
start the process. A smaller turbo will start the process quicker, but
will not be able to move as much air as the larger unit. A supercharger on
the other hand since it is directly driven by the crank will nearly always
have available boost, but it consumes a large amount of engine energy, much
more so than the turbo.
Nicholas
At 10:50 AM 3/9/98 -0500, you wrote:
>> > > on that same note,, is it really possible to set up a supercharger
with a
>> > > clutch?? (remember MAD MAX ??) that would be kinda cool... it would
even the
>> > > drivability differences mentioned below....
>
> FWIW, the blower on that Interceptor in the Mad Max movies was not
>functional. It was a shell for looks only.
>
> Although that begs the question as far as what the driveability and
>performance impacts would be with a disengageable supercharger. Wonder if
>anybody has used an electromagnetic clutch to find out? I have a feeling
that
>a freewheeling Roots-type blower would be mighty disruptive to the intake
>system, negating any advantages derived from the ability to disconnect it.
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