Predator 212cc engine stuff

I have been thinking about getting a new Predator 212 for my go-kart and was thinking about doing some mods to it. I am wondering how much extra power buying a stage 1 kit adjusting the throttle screw and removing the governor will get me or if I should just buy a higher horse power/displacement engine.
 

flattop1

Dawg 89
Racing kart or off road vehicle ?
Off road the bigger engine .
 
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