On Mon, 11 May 1998 04:56:07 EDT
LBPB1 <LBPB1@aol.com>
wrote: Subject: judson supercharger
Does anyone know anything about Judson superchargers ? I havd one that
was being thrown away. I grabed it up with the intention of using it on a
Spit. or even my GT6. The manifold I have for it bolts to an MG migit and the
carb is a single down draft unit of unknown origin. Can anone give me an idea
what kind of boost this thing makes and where parts can be found. I understand
it needs an oiler which was missing from the system. Any info would be great.
Thanks!
PLB3
Well, I don't have much on the Judson Unit, but I know that some of the
folks,(Bill Burroughs & Paul Smock), in the SCTOA (Southern Californian
Triumph Owners Association) had one in their possession a few years
back,(April 1992).
I will copy this mailing to them so they might be able to respond to you
directly ???
I recall that their unit was intended for a TR3, but that's all I can
remember...
These units were made by Judson Research and Mfg Co of Conshohocken, PA.
(I have no idea if they are still extant, but probably not.)
I have seven pages of photocopied information, (which you might be able to get
more easily from SCTOA, but if not, ask me, and I'll send you some photocopies
of what I have),(NO, not everyone on the list please!).
As to you query about 'Boost' Pressure, I will quote:
"The Judson Supercharger replaces the vacuum in the manifold with a pressure
in proportion to the load placed on the engine. There is always a vacuum in
the manifold when the engine is at idle, or when the engine is not under load.
The vacuum in the manifold is replaced with a pressure as the throttle is
opened and the engine is placed under load. Highest boost pressures are
obtained under full throttle operation when accelerating or going up an
incline. Pressure will vary according to condition of engine, altitude, speed,
humidity and engine load.
Maximum manifold pressure, because of these conditions, will vary between 5 to
6 pounds. Even when the engine is not operating with a manifold pressure at
idle or when there is no load on the engine, the efficiency of the engine has
been increased due to the improvement in volumetric efficiency. There is a
direct relationship between fuel consumption and manifold boost as horsepower
available increases with the boost pressure. When you do not use the
additional power afforded by the supercharger by pushing the engine, you do
not pay for it through increased fuel consumption."
Well, that's the blurbs rather long winded (no pun intended), way of saying
that
1) The harder you make the engine work, the more boost pressure you get.
(True)
2) Pressure varies depending on operating conditions (True), and is no more
than six PSI/half an atmosphere, as is common with most low-pressure
superchargers.
3) If you 'put foot' you'll go faster but use more gas! (True)
Finally, having run a Shorrock Low-Pressure Supercharger on my Triumph Herald
over a two year period (April 91-April 93) and 20,000 rip-roaring miles, I can
vouch for the fun factor, but be aware, it will need to be correctly mounted
so as not to place undue wear on any other engine components, or the bolts
holding them on. And, most importantly, even at relatively low boost pressures
of 6 PSI, your compression ratio will rise quite dramatically and place a
severe load, and vastly increased wear and tear on all reciprocating parts of
your engine, but especially the pistons, (my last set of reproduction alloy
pistons only lasted 2087 miles, which is why I sold it, as I couldn't afford
to buy proper forged pistons at over 160 USD each.
Oh yes, you'll also need a triple-core competition water radiator to deal with
all the extra heat generated along with all that extra power! Remember that
65% of the energy produced by the gas turns to heat, and if you double the
power output, you'll more than double the heat output !!!
A big fat oil cooler might not go amis either...
But was it all worth it ?
YES, YES, YES !!!
Good Luck,
Leon F Guyot
TSSC International Secretary
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