balls to the wall(s)

What is balls to the wall(s)?

balls to the wall(s) meaning in Military or Military Slang terminology / glossary / dictionary is:
(U.S.) To go as fast as possible. (From aviation and nautical; pushing all engine throttle levers toward firewall.) Full throttle causing the ball weights of the engine govenor to open outward toward the walls.

 

reference: Glossary of military slang