By speed up the machine are you refering to ground speed, cutting speed or cutting head swing speed? Does this machine have the auto sweep feature? If so near the computor under the tilt out lid covering the battery & tool box you will find a spade type fuse. Remove the fuse and it will disable the auto sweep and speed up your swing speed. If you are wanting to speed up all of the hydraulics (Swing speed, Ground speed & up and down speed ) replace the pulley on the hydraulic pump with a pully about a 1/2" smaller diameter. This may require a belt change. Hope this helps.
Gordy