pictures of pedal assemblies 340 vs. others
The only part you can Change the lenghth of without Messing with the location of the pivot points is the Pin spread.
Changing the length of the Z-bar lever that pushes on the adjustment rod will stiffen the pedal if made longer or easier if made shorter. BUT! this will wear Parts by pushing on the fork at the wrong angle.
Sure it will work but for how long? Changing the pin spread is really the only way to change the Geometry without affecting the operation of other parts that would cause eccesive wear. Been there done that and learned the hard way. One of the reasons I started this thread.