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Turbocharged, Supercharged, and Hotrod Motorcycles: [turbobike] Dirt cheap supercharger

[turbobike] Dirt cheap supercharger

Phil Dorman (watin@hunterlink.net.au)
Wed, 15 Apr 1998 13:13:28 +1000

This was posted to the McMod list by 
 Steven A.Richmond Sr. <richmond@RICHMONDLABS.COM>

    OK, here it is.  Please don't laugh until you've tried
this, it really works.  We've used these things for many
different jobs where we needed a lot of volume at low- to
moderate pressure levels, and they almost always work out
very well.

    All you need is a "smog pump"!  I assume everyone knows
what I am referring to.  In the USA, at least, almost every
new car has been required to have one of these since around
1970, (by government regulations) to pump air into the
exhaust manifolds, which supposedly facilitates more
efficient conversion of the unburned hydrocarbons as the
mixture passes through the catalytic converter.

    If we build them into a machine, we by them new, but
there are piles of them in junk yards which you can actually
get for as little as $5.00 each.  People don't realize just
how efficient these little pumps are.  At 8,000 rpm you can
feel a strong air blast from a one inch pipe attached to one
of these standing over twenty five feet away, they will
actually produce up to sixty pounds or more (for a VERY
short time), and if you block the air flow completely the
pump will stop a five horsepower electric motor.

    Most of them take in air though an impeller right behind
the drive pulley, which is fine for most purposes, but some
are equipped with a separate inlet port complete with a
small air filtering device,- which can prove useful in
certain circumstances.

    You can even hook these things up "back to back", and
the first one will drive the second,- with amazing
efficiency.  If you get the kind equipped with both inlet
and outlet ports, you can the make a closed loop and either
one will drive the other,- in either direction.  There's a
novel way to transmit power!  If you do try this, be sure to
include an intercooler in the plumbing,- the only thing I've
found that will ruin these pumps, is heat!

    Some of the pumps I'm describing have more capacity than
others.  I like to play with the ones from 350 cid Chevrolet
police cars, or 454 cid trucks.  It takes four to six of
these to provide ample boost for the average V8, but one or
two should suffice for most motorcycle engines.  I built a
setup using these on a small V8 once, and used a automotive
air conditioner pump, electric clutch & pulley, so that it
was not necessary to wast fuel driving the arrangement until
it was needed.

    90% of the pump body is aluminum, so they are relatively
light, and it's not difficult to polish them up and
radically alter their appearance.  By the time you've done
that, and added a aluminum timing pulley,- no one will ever
guess what it is/was, or how little you have invested.

Be careful how much intake pressure you apply to a high
compression engine.  You probably shoudn't try to go over 8
- 10 pounds on any engine with a 9 :1 compression ratio or
higher.  We attached one of these to a friend's son's
go-cart engine (Briggs & Stratton) and the power increase
was very impressive,-- the kid decided he'd like even more
power, and changed to a larger primary pulley.  I'm not sure
if it was  the extra compression or detonation, but it
didn't run very long after that before the complete cylinder
assembly separated and exploded off the engine block (no
kidding!),-- kind of reminded me of pictures I've seen of
Blown(up) top fuel drag engines.

    If anyone is not familiar with these types of pumps, or
has any trouble understanding how they can be attached,-
driven, etc..., let me know, and I'll post a photograph of
one mounted on a prototyping test setup.


--
 Steven A. Richmond Sr. < RIEL inc. >
 richmond@richmondlabs.com
 http://www.richmondlabs.com




------------ Regards, Phil Dorman. ------------
Email watin@hunterlink.net.au
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