07/07/2003

Buick Dual Path

Looking at an old Chilton reveals only one planetary gear, no bands, and
several clutches.  The output turbine is welded to the ring gear.  Reverse is
accomplished by taken the stator as an output.  The fins are for air cooling.

The torque convertor has a ratio of 2.4 to 1 maximum.  The planetary has a
1.58 with a total torque multiplication of 3.8 to 1 at stall.

It looks like a solid one piece drive shaft from the sun straight out the
back.

There is also a clutch from the engine.  It looks like there is both a direct
and hydraulic path and the book says the convertor has both a mechanical and
hydraulic path thru the transmission via the convertor clutch.

Since the rotating assembly is extremely small, it should be capable of
handling a reasonable amount of torque.

The lighter the vehicle, the hardier I think it would be.  Tires make
excellent fuses.

Of course, since I know nothing, the idea of an extremely small rotating mass
transmission with a strong shaft and no bands and only one planetary means I
have no clue.

------------------------

Figure it has about 1/3 the rotating mass of a power glide.  Powerglide has
two band held ring gears which spin in locked up Direct Drive.  Plus at least
as many clutches etc.

Since the planetary is integral with the torque converter and the ring gear
permanently attached - even less weight.

Side by side, the powerglide is HUGE and HEAVY compared to a Buick Dual Path.

-----------------------

Chilton shows a solid, large diameter shaft from one end to the other.

There are no gears in the "transmission" chunka behind the torque convertor -
its just a housing for the pump, two clutches - one for the stator overrunning
and one for the sun gear overrunning.  Also the governor and the parking pall.

That's all in the tranny kids.  Think of all the gearing in the t-q of a
powerglide and virtually nothing behind it.

The planetary is in the transmission and driven by the ring gear bolted
directly to the turbine.

The one piece shaft looks largish compared to a hand - larger than an AOD
appears to be.  Looking at it closely shows no apparent weak spots.

Looks good to about 400 or more hp.  More than enough for a hot 215 or 3.8 V6
six in an MG for example.