If you need more power then you likely need a bigger tractor.....Adding power to a pickup that runs wide open for short bursts at a time is different that adding power to a tractor that may use it continously in plowing or thru the PTO shaft.If your going to add power,the best way is with a turbo if its a N/A engine,then add a little fuel to match the increase in airflow.Just turning up the fuel will give you a little power,but create high EGT's and black smoke.Remember there is no free lunch a modified,higher hp engine will wear out faster and be less reliable than that same engine at stock power levels.