Yea the justock is fixed timing and pretty slow because of it. Thinking about swapping the turnigy setup in the 22? You can, but only if you're just practicing on the track or racing in a open/mod buggy class. If your local track only runs 17.5 stock, or locked timing class it would be better to stick with the Justock, due to rules. Lol. But if you do swap in the turnigy system, I would put a fan on the esc (and motor) if there isn't one already, keep in check of temps and gear down on the pinion since it is a bigger (kv) motor. I would gear down to like a 21T pinion and if it's cool enough and if you want to gear up you can.