65 the good bad and ugly
Isnt it true if the kickdown linkage isnt set up right it will burn up the trans? Only asking cause I run 4 speed and truly dont know. I have heard this though, many years ago about Moapr automatics. In other words, I dont think id drive it without the kickdown linkage set up proiperly.
With stock valve bodies yes; if too much torque is pumped into the trans. You can still drive them granny-like tho.
The KD mechanism is a misnomer.That mechanism is actually controlling the the main pressure in the trans; the further you press the gaspedal, the higher the pressure goes to keep the clutches from slipping excessively, which will burn them up.
On early models when the pressure reached max, the trans would kickdown one gear.
On later models, there was a Part Throttle feature which allowed the kickdown to occur earlier.
The Line Pressure is the controlling force which sets the minimum pressure, and is adjustable with the pan off.
A modified valve body(usually for racing) MAY have been engineered to not use the KD mechanism, or the mech will be tied back to the max, at the trans lever. In these cases the carb linkage no longer affects the valvebody, and so, can be eliminated. The high LinePressure tho is a PITA tho for a streeter..... IMO.
Other brands of automatics also have to deal with the shift quality at various load settings. Years ago they all used some kind of manifold vacuum sensitive shift modulators.
On a GM for instance, tho, the difference was that their system worked in reverse; the high manifold vacuum caused softer and earlier shifts.And low manifold vacuum caused higher rpm and harsher shifts. So if the vacuum signal failed, the trans just shifted later and more harshly, alerting the driver, and without trans damage..
IIRC, the early Fords worked in the same fashion.
