hop up

Short definition from Wiktionary

Verb

1. 1
   To excite (people).
2. 2
   To get in a high vehicle.
3. 3
   To stand up quickly.
4. 4
   To make something, especially a machine, better (faster, bigger etc.); to soup up.
5. 5
   Used other than figuratively or idiomatically: see hop, up.