For you 97-03 guys im not sure about the pre 97 check this out Over time the throttle cable can stretch causing slack in the cable and loss of throttle response. Not a problem anymore, will also work on 89-97 rangers.(also did it to my last truck 1990 Ranger 4.0) Throttle Cable Zip Tie Mod

 

I actually just did this today. It takes all slack out of the pedal. I used to push the pedal down at least an inch before it did anything and now the pedal is firm. Makes it easiers to drive, not sure if it really does anything for power, but I think it is more comfortable.

 

my thinking is this if the cable is "streched" and you floor it that means that the Trottle Body isnt opening all the way. by taking the slack out will allow it to open as much as it can. I know before i did mine it would only pull to about 4500 then bog for a minute then shift now it goes all the way to 5

Flex