DIY_EFI Digest V4 #85

[Greg Hermann]

>On Thu, 4 Feb 1999, Greg Hermann wrote:
>
>> >Re: TC's and manual trans (was: Re: Smooth strategy)
>> >
>> >
>> >
>> >
>> >>>No way--a two element torque converter is a violation of Newton's laws!!>>
>> >
>> >>>Regards, Greg>>
>> >
>> >Greg
>> >I don't know much about Newton's laws however I have been under cars for
>> >the last 45 years, working mostly on auto trans. so I know a little bit
>> >about torque converters. To get torque multiplication in a 2 element TC
>> >you need curved vanes plus a  different number of blades (vanes) in the
>> >turbine and impeller. There was usually a split guide ring (doughnut) as
>> >well. While this arrangement is not as effective as a TC with a stator
>> >it nevertheless multiplies torque and is therfore correctly termed a
>> >Torque converter.
>> >
>> >Theo from downunder
>>
>> Let's don't mistake slip--lock-up speed  characteristics for torque
>> multiplication. If you have torque A coming into the unit on the input
>> shaft, and torque B going out of it on the output shaft, For A to be
>> different from B, there has GOT to be a torque reaction against the case.
>> No way out of it. Otherwise we are talking about a close kin of the famous
>> (?) 300mpg carburettor!
>>
>
>Actaully I think this is how it works.  The reason it multiplies is
>much simpler, rpmin != rpmout.   The easy model is more like
>rpmin*torquein = rpmout*torqueout*efficiency.   I don't believe there
>is a torque reaction against the case (except waht is actually
>decreasing efficiency).   Basically if rpmout is 10% less that rpmin,
>then you could boost torque by an appropiate amount to make the
>quation balance out.   Also generally this is probably a max torque
>multiplication which may complicate the model above more, but I have
>used this model in some program I have written and it is pretty
>accurate with street convertors, with the high slippage convertors the
>model above does not work exactly right.     It is really no different
>that having a gear that multiplies torque except it is less efficent
>and somewhat more variable on the multiplications.

A manual tranny has a torque reaction when in other than direct drive--you
are just not aware of it, cuz the bell housing puts it into the engine and
thence into the motor mounts. OK--consider--when you have a busted motor
mount with a manual tranny--is the engine more likely to lift up off of it
in first gear or high gear when you jump the throttle?? Same principle. The
manual tranny puts its torque reaction into its case via the countershaft
(layshaft in Brit-speak) bearings when in a gear that multiplies torque.
There simply HAS GOT to be a third, reaction element for torque to either
increase or decrease in a transmission, coupling, or torque converter of
any sort. Doesn't matter what the speeds are doing, input torque, output
torque and reaction torque must sum to zero. Don't know how else to say it,
let alone be any more plain about it!!

Regards, Greg