would adding a fireslot style head to the fource engine increase power output? it certainly seems to work for the racing kart boys. i am talking custom made head here. i work at a machine shop so i could make one, i just want to know if its worth it to try.

engine will be run on gas/glow (probably just high test fuel and 'heet')

any thoughts? carb will be a 11.11 dual needle with the spring in the pump

The kart guys sometimes mod the stock head, you may not have to make a new one. But unless you improve breathing its kind of pointless.Simply bolting a bigger carb won't do it.