Thanks, Randall,
Just the info. I was looking for; makes me think twice now! I never
intended it for the TR as, contrary to the 190SL, I find its power
quite adequate, but I would be very interested in your Judson
project when you get around to it. I have been communicating with
Haddon Judson Jr. who highly recommended a George Folchi as being the
expert for adapting, rebuilding of, and parts and advise for, vintage
Judsons.
See you at the Triumphest?
Hans
On Sep 1, 2011, at 1:08 PM, Randall wrote:
>> Does anybody have recommendations and/or experiences with Judson
>> superchargers? I am actually thinking of picking up a rebuilt one for
>> my 190SL.
>
> Unless being period correct is important to you, I would highly
> recommend
> using a Roots-type blower instead, preferably with a "priority
> valve". The
> Judson blower design is considerably less efficient, which means it
> both
> sucks more power and heats the intake air more, which in turn makes
> detonation much more likely. And detonation can literally destroy
> the motor
> in a matter of seconds!
>
> The Judson uses phenolic vanes (although perhaps yours will be
> rebuilt with
> a more modern plastic) that wear and shed particles directly into
> the engine
> intake. The original TR and MG setup (likely your MB will be
> similar) is
> also a "full time" blower, meaning it is always compressing the
> intake air
> (and drawing significant power) even when it is not needed (throttle
> plates
> are closed). The modern designs use a "priority valve" to bypass
> the blower
> when it is not needed (and some even have a clutch to let the blower
> stop
> turning altogether).
>
> Because of the rubbing contact surfaces inside the Judson, it also
> requires
> a steady supply of oil through the intake. Although the original
> oilers
> were made by Marvel, the oil should be motor oil, not Marvel Mystery
> Oil.
> The oil also tends to promote detonation.
>
> All that said, I do have a TR3 Judson stashed away, that I hope to
> be able
> to try out some day. Most likely I'll also install water injection
> and
> boost retard, to control detonation.
>
> PS, the factory MB superchargers are Roots-type, made by Eaton I
> believe.
> Some of them include the priority valve right in the blower housing.
>
> -- Randall
>
>
> triumphs at autox.team.net
>
> Donate: http://www.team.net/donate.html
> Archive: http://www.team.net/archive
> Forums: http://www.team.net/forums
> Unsubscribe/Manage: http://autox.team.net/mailman/options/triumphs/tr3 at
> roadrunner.com
|