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February 28, 2003

Let me tell you something, I wish to hell
it was possible to run a Judson on today's
unleaded premiums.
I worked my tail off for 2 years
to get this to work as did a buddy of mine
who lives in Holland. Have been a member of the Judson List for more
a few years now.
Based upon the promise of Delrin vanes
from the USA Judson rebuilder, I even
had my new Rivergate engine "tailored"
for this blower. That's how much I was
into this application. I figured with self-
lubricating vanes, 2 stroke synthetic oil
and a "drip" system of alcohol/water "T"'d
into the oil feed line to the blower's intake
manifold, along with an Aldon "computer generated" ignition curve based
upon 93PON and my engine spec. that I stood
a fighting chance of making this work.
I got an alum. rad, alum. head, louvered
my bonnet and set up a "vented" hole
in the bonnet for outside air induction
as well. I so into this it was sickening!! :)
Used "Total Seal" rings and an original
EN40B steel crank as well. Of course,
none of this goes to waste, either. I've
got a Cooper "s" spec. engine that positively goes like hell and will go
better when I convert over to my 45DCOE
this Spring.
But man, I wish the Judson had worked!
You would not believe how quick the stock
1275 was (PO'd '67 Spridget) with a 6psi
boost curve superimposed on the stock
ignition advance curve, "shortened to
25 degrees total advance. Momma mia,
I loved it. Super "quick". With the Datsun
5 speed, the plan was a change to the
3.55 diff. and competition half shafts next.
When the Delrin vanes fell through and
the Judson guru looked like he wasn't
coming through with an alcohol/water
delivery system....well, that was it.....
I returned the Judson and got my money
back. I hated to give up but I needed his
cooperation to make it work. I know my
stuff when it comes to this application
'cause I made it my business to do the
research and personally "walk the walk".
I know of no one that has gotten the application to work successfully on
modern unleaded premiums, on ANY
capacity Series "A" engine used as a daily
driver, except to a limited extent in winter
temperatures of between 30-40F, or below, including the 948 8.3-1 engine
which it was originally designed. Today's
octanes just can't hack it without retarding
the ignition to the extent the stock car would be as quick, if not
You either need the octanes the application was designed for or you need
alcohol/water (delivery, not injection) to
"cool" the combustion process down to
the extent you can run today's unleaded
91-93 pump premiums. This would work.
They used this stuff in WW2 for extra
power (along with nitrous) and I've used
it in aircraft such as the Fairchild or
Swearingen Metro 1 for hot weather ops.
or as an "emergency" thrust producer
in engine-out operations. This stuff delivers the goods, for sure.
Believe me, I wish this was not the case
and I could get it to run on 93PON with
a little octane booster...no way, Jose! :(
For a guy who doesn't mind filling up
with Sunoco CAM2 112-118 or Turbo
Blue, etc., fine. Or the guy with the show
car or the guy who takes the car out now
and then and uses racing fuel, fine.
Otherwise, the more expensive, modern
lobe-type "complete" kits are definitely the only way to go, IMHO.
Expensive....yeah....but they work, and
that's the objective, right? Right!! :)
Meanwhile, I've advised the Judson guru
that with the exception of very limited use
as mentioned above, he's basically out
of the Judson business as far as Sprites
are concerned.
Now.......If there were more of
the larger capacity MGA sized Judson's
around, Spridget conversion parts could
be fabricated accordingly and because
the application was designed for 1500-1600cc engines, it could be very
much "underdriven" for a 6psi boost curve
for a 1300cc engine....far less compression/friction heating and a fair
shot at superimposing a 6psi boost curve
on the stock ignition advance curve (this
is what gives you that 40% increase in
torque for the street) using today's unleaded pump premiums, maybe with
a little octane booster and some cooler
outside air for induction.
Cap'n. Bob (Ret'd)
'60 Frog

PilotRob@... 19674

Posted on February 28, 2003 05:10 PM
Posted to category(s) Body | Carburetor | Cooling System | Cylinder Head | Drive Train | Engine (external) | Engine (internal) | Exhaust System | Forced Induction | Fuel System | Gauges | Ignition System | Intake System | Lubrication System | Miscellaneous | Racing | Restoration | Specifications | Suspension & Steering | Technical Info | Transmission | Tuning

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