I have a mp9 tki3 rtr with the ke21r engine. I’d like to go with something with a little more pep. Caveat: I wanna stay pull or Roto start. I just bash so I can’t justify buying starter box, batteries, flywheels, engine mounts. What’s a good upgrade from the stock motor with a pullstart available. I’ve looked at the lrp engines but don’t know if they will just blow my diffs out.