[TR] Superchargers

[Hdefer]

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
>
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