There are two "force-relationship-things" going on here, and I don't think I was clear enough in my posts above distinguishing between them. First, there's the relation between the motor's torque and the reaction torque in the chassis. Then, there's how that reaction torque is realized as weight transfer between the chassis and the ground. The first of these has nothing to do with the location of the motor relative to the chassis (as long as they're rigidly connected), and I can prove it to you. The second is affected by weight distribution, suspension set-up, and everything else, and its this second part that most drivers are more familiar with, I think.
The first of these relationships, between the motor and the chassis, is independent of the motor's location in the car as I laid out in my first post. More simply: on any acceleration, the motor exerts a torque, or twisting force on the car. The motor and the car are rigidly connected; since the motor can't twist in the car the car has to exert an equal and opposite torque on the motor. Since these are equal and opposite, the length between them cancels out of the equation - the length term doesn't matter. The torque interactions between the car and the chassis - including whatever effect changing the motor's direction has - are constant no matter where the motor is located.
The second interaction, or torque-relationship, or whatever you want to call it, occurs between the chassis and the ground. If there is no ground, the chassis' torque is realized as rotation - the "gyro effect". On the ground though, we have a similar situation to the above, this time the car exerts torque on the ground and the ground "pushes" back. The difference here is that the two are not rigidly connected - there's suspension, tires, etc. between them. Because they can move relative to each other, moments of inertia (essentially the weight distribution, including where the motor is), spring rates, suspension settings, and all that other stuff become important.
So... the location of the motor does not affect the magnitude of the torque between the motor and the chassis. It does, however, affect how this torque is realized through the suspension and in the way the car drives.
Whew. That's been about an hour or so, but I'm confident about it - I hope it makes sense. Time for bed.
Oh, and Roger, thanks for the kind comments! Very much appreciated, glad you liked it.
__________________
|