TC's and manual trans (was: Re: Smooth strategy)

[Shannen Durphey]

Greg Hermann wrote:
> 
> >Shannen Durphey wrote:
> >>
> >> If you have any chances to roll around some of the car shows with well
> >> restored examples from the early 40's to late 50's, you'll see that
> >> the upper scale cars were designed to be very smooth.  In the
> >> transmissions, there were vacuum powered clutches, variable speed
> >> transmissions, standard trans with torque converters. Even
> >                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> >
> >Oooh!, the magic words.  I was just about to ask about this.  Can
> >anyone give me some info or point me to a source about torque convertors
> >and how exactly they work.  Are these tightly interdependant on an
> >automatic trans (because of the fluid used) or could they possibly be
> >used independantly?  I.e., adapted for use on a manual trans.
> >
> >Forgetting for the moment about the specific machiningg, adapters, etc that
> >would be required to physically hook it up, is it possible or feasible
> >to make it work outside of an automatic trans?  Is it's hydraulic fluid
> >supply sealed inside the convertor?  Could you fill the convertor and
> >seal it and expect it to work for very long or does it need a continuous
> >flow of fluid for cooling?  If so, would pressure need to be modulated
> >for any reason or does it just need a continuous flow?
> >
> >thanks for any info
> >--Dan
> 
> Don't recall whatinell they called it, but for a while Porsche used a fluid
> coupling AND a vacuum operated clutch (which was triggered by a microswitch
> on the manual shift lever) in front of a manual tranny in the 911's. The
> fluid coupling ran in engine oil, IIRC. (A fluid coupling does not multiply
> torque, has only two elements, called pump and turbine.)
> 
> Easiest way to think of how one works (at least for me) is to think of a
> centrifugal pump driving a centrifugal turbine--and then eliminate the two
> housings, and all the attendant weight and inefficiencies, by just wrapping
> the impeller and turbine wheels into a taurus shape, and mounting them face
> to face.
> 
> Regards, Greg

1952 Dodge or Chrysler had TC+Manual.  In order to engage gears or
shift you used the clutch, but once you were in gear, you didn't have
to press the clutch again.  Pretty fragile, so say those in the know. 
Legendary Tucker had torque converter at either rear wheel.
Big difference between torque converter and fluid coupling is the
addition of the stator, which redirects fluid from the "turbine" above
back to the "pump" in the direction of pump rotation, multiplying the
effective torque of the engine.

Don't know many details about the Chrysler setup,(just some old
stories) but auto trans' TC gets fluid from the transmission, and when
there's a heavy load applied, there's a lot of heat generation going
on there.  Lotsa mechanics have seen overheated TCs that have become
discolored.  Those designs need sufficient cooling.  Vegas had holes
in the trans housing and a fan spot welded to the converter to
circulate air.

I'm looking at a reference book called "Automatic Transmissions", by
John C White, ISBN# 0-8273-2606-8, which has good torque converter
info.  There are past issues of "Cars and Parts" which discuss the old
Dodge transmissions pretty heavily, although there seem to be a few
variations on that one.

The reverse of this is a clutched automatic, which for racing would be
fully manual.
Shannen