I thought the wide open throttle boxes were ment for electronic motorized throttle bodies. Unlike our direct mechanical cable throttle bodies.
The motorized throttle bodies dont open like a mechanical one does. Mechanical is direct to the foot where as motorized is controlled by the computer to be at the best optimized position for torqued output. Even if your foot mats the pedal to the floor, the throttle body isnt necessarily wide open, but is at the optimal position to keep a balance of low rpm engine vacuum and the power demands you are asking from it, which in return keeps torque strong as rpm's climb. A mechanical throttle body opens wide killing engine vacuum and torque together untill the higher rpm's
If you want more of a tip in throttle response, a good tune is what you want.