Overdrive Options

In many cases i would agree with you Matt. Those were just general numbers i used for a example. Reason i brought it up is that the older square faced cars tend to push more air then the modern stuff. At some point there are diminishing returns to lowering rpm. When you get to that point it requires more throttle opening to maintain speed. If it gets too bad, excessive TCC disengagement and even downshifting can result. The terrain where the majority of use is can also play a role.
If you were to use an aftermarket controller TCC and od are adjustable your call, just plug a laptop in and adjust away. Most of the modern day autos don't have that steep of an od ratio, I think the 200 has the most at .67. This transmissions are obviously not for every one. If you live in the mountains and are driving around in a /6 car than obviously these are not for you. But if you throw the torque of a v-8, and any sort of performance gear ratio things change. For a brief while I had a 4x4 F150 with a bit of a lift. 33" tires, 4.56 gears and an e4od. Had a 351W under the hood, built for mid range power. Truck had no troubles staying in od with the tc locked up at any speed over 50 mph. Thing was about as aerodynamic as a barn....When throwing an od and a lock up tc into the equation it becomes even more important to build the car as a complete unit, not just a motor......a trans.........and a rear end.......Spend some time at the LS1tech forum, or any one of the newer Mustang forums and I bet you will find more folks running an od/lockup or in the case of a stick an od than not....