1993 Marathon 36volt need lil more speed

Hey everyone new to the site. I have a 1993 marathon a few cosmetic modifications but no speed modifications that I am aware of. My current top speed is 13 via gps and I am looking to get up to at least 25. I am basically looking for the most bang for the buck. I want to keep the 36volt set up but I am not sure what direction to go controller, motor, or gears? I have never had an electric vehicle so this kind of set up is very new to me.

5.5" lift
air shocks up front
23" tires


Thanks,

HZ

Attached Images

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