My Cruze gets the most takeoff power at about 40-50% down on the gas pedal. When it gets to about 4th or 5th gear I can push the pedal down further and it increases power. But it's still better when I don't push it all the way down. Everything (including throttle) is controlled by the ECM, so it must have been programmed this way. I refer to pushing the gas pedal instead of opening the throttle because I don't know how the ECM controls the throttle, or if putting the pedal to the floor creates WOT.