Quote: You still need to have a kickdown for the transmission. With the 4L60E it is probably a throttle position sensor because the ecu needs some way of knowing how hard you're pressing the gas.
As for the low first gear, well a heavier car and/or a numerically lower rear end gear ratio like a 3.55 or lower will benefit the most from the steeper first gear of the GM trans.
I would use the TPS sensor on the 6.1 L for the "kick-down" on the GM trans or a manual Valve body on the 727 and eliminate the kick-down altogether. If I am running 3.73 gears will that first ratio be too steep? It would act like a 727 with a 4.65 geared rear.
