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On the topic of superchargers



Steal one from an AC compressor.
----- Original Message -----
From: "Mike Blain" <rept@qwest.net>
To: <scirocco-L@scirocco.org>
Sent: Wednesday, April 24, 2002 7:06 AM
Subject: On the topic of superchargers


> My engine sits at Momentum's shop in Canada- and I have all the
> components in place to turbo or Supercharge at this point. As it sits i
> can expect 175+ HP from my lil 2L.   What I'd like to do is find and
> install one of those clutched on/off superchargers so that the car is
> manageable under normal aspiration and yet- I can achieve boost when
> needed at the flip of a switch.
> Last year I saw one of these devices on Ebay for 500. It was for an MR2
> (?). Does anyone on the list know of any Clutched Chargers still being
> manufactured, that will work for my purpose?
>
>
> Mike Blain (don't make me dish my pistons punk)
>
> Noah wrote:
>
> >>1) Superchargers are easier to deal with and support
> >>as a manufacturer. I would argue that Neuspeed or
> >>Jackson racing has far fewer "customer complaint"
> >>(what I might call "customer stupidity") issues than
> >>Greddy. The fact that boost levels are not directly
> >>related to crankshaft speed creates a LOT of issues
> >>that the average person can't deal with and tune for
> >>properly. Wastegates, fueling, timing, etc. are all
> >>more difficult to manage when you cannot directly tie
> >>air consumption to engine speed. Couple that with the
> >>millions of stupid people out there, and you see why
> >>there are relatively few mass-produced turbo kits.
> >>
> >
> >     I read all that as saying "Supercharger kits are more proprietary
and
> > thus pretuned to certain boost levels, therefore easier to set up but
less
> > flexible." That is not really something I am in favor of.
> >
> >     As far as using a G-lader based supercharger setup transplanted from
a
> > corrado, I would urge you to reconsider. The G-lader is just not
reliable
> > enough. With stock boost levels it doesnt make good hp and if you go
much
> > over stock you are asking for trouble. As for the alternatives, the
horror
> > story I referred to was a Lysholm (sp?) kit for the corrado. This thing
is
> > totally underwelming powerwise, and the bearings in it are SO loud they
can
> > be heard above the engine.
> >
> >
> >>2) The reason I personally am going with a
> >>supercharger is due to the intended purpose of my
> >>vehicle: autocrossing. The nature of autocrossing
> >>means that instantaneous throttle response and a
> >>linear torque curve are FAR more important than
> >>efficiency and maximum power potential. I'm wondering
> >>how in the world I'm going to get 200whp hooked to the
> >>ground...300whp in a 1900lb car on an autocross would
> >>be completely unmanagable and slow me down. I also
> >>need to be able to apply power whenever I want, *NOW*.
> >>There are people who are pretty successful at planning
> >>in advance for turbo lag on an autocross, but it is
> >>definitely not an ideal situation. If they make a
> >>slight mistake in their timing, it costs them several
> >>tenths of a second to correct, then potentially a
> >>second or more to get the boost back up. That's the
> >>difference between an easy 1st place and 10th at a big
> >>event.
> >>
> >
> > hmm. When I go to the autocross the two biggest stars there are the
> > mr2...turbo, and the late gen rx7... turbo. Not to mention all the
> > turbocharged miatas... When you are on a track and you are reacting
solely
> > to the track and not other cars, the turbo shouldn't hurt you a bit. In
fact
> > the lag (what little there is in any modern turbo car) will help you
stay
> > hooked up, and even keep you from breaking your car. As you know, it's
much
> > more important to be smooth than to be fast.
> >
> >
> >
> >>Additionally, having a direct relationship between
> >>throttle position and power output is a huge
> >>advantage. I've talked to enough Supra drivers to
> >>understand the issues created when you're navigating a
> >>long-ish sweeper or a slalom at part throttle in a
> >>big-boost turbo car. Just about the time you've set
> >>the car up nicely for the turn, and balanced the
> >>brakes, throttle, and steering on the head of a pin,
> >>20psi of boost comes rushing in to mess it all up! At
> >>3500rpm a Supra might make 150whp...but 1/2sec later
> >>at 3600rpm it could be doing 350whp! There is NO
> >>in-between. Managing that situation definitely takes
> >>time/attention away from driving faster.
> >>
> >
> > So you are saying that he couldn't let off the gas and get thru there in
the
> > same way you would? I'm not sure I can make any kind meaningful argument
in
> > this example. Far too many variables.
> >
> >
> >
> >>And on top of it all, my rough calculations indicate
> >>that, presuming the same intercooler size/location, a
> >>G60 setup is probably at least 15-30lbs lighter than a
> >>turbo. The G60 itself is only about 15lbs, there's
> >>much less plumbing, no extra manifold weight, no
> >>wastegate (well, the bypass valve on the TB weighs a
> >>few ounces, I suppose), etc. When you rely on light
> >>weight to beat 600hp AWD cars, 30lbs does matter.
> >>
> >
> > I tend to think the two systems would be basically the same weight, the
only
> > real difference is the wastegate, and it weighs maybe 5lbs. Regarding
> > plumbing - with a turbo I have one tube running from filter to turbo,
one
> > from turbo to IC, one from IC to intake. You will have one from filter
to
> > blower, one from blower to IC, one from IC to intake. You will have to
move
> > something (Alt, AC, etc) to the back of the motor or delete it, whereas
I
> > can mount all my aux stuff in common locations. Not sure how you will
mount
> > the intercooler from the corrado, but it's a pig anyway, you'd be better
off
> > with an aftermarket one, of course if you do that you will be making
custom
> > intake hoses, something you seemed opposed to.
> >
> > Question: which VW chassis are you considering for the swap? A2? If you
are
> > determined to have a Golf with a G-lader, maybe you would consider
buying
> > one already set-up? There's one here that belongs to a friend of mine.
He's
> > a mechanic with too much going on to mess with it. He's got about 5k in
it I
> > think. It has been described as "Too fast for that chassis" - He bought
it
> > as a track car from another local dubber. That might be a good deal for
you
> > after you consider the expense of all the stuff you will need. Looks
like
> > the guys did a pretty good job on it too, I've seen it first hand a
couple
> > of times, but I've yet to ride in it. In NC if it's of any interest.
> >
> > -Noah
> > -86 Audi 5ktq
> > -84 Audi Quattro
> > -82 Chevy Rollback wrecker! 454cu yeehaw!
> > -Yard full of VWs that will become one car soon
> >
> >
> > _______________________________________________
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> >
> >
> >
>
>
>
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