Let have a show of hands from the guys that would be willing to pay 1000.00 to 1500.00 for a cylinder and head kit for a LT 250 or a LT500.

About $600 for porting, $280 for welded ears and decking and $200 for head mods... My hand is way up!    Gas power valves please.

You do not want a exhaust pressure activated power (pneumatic activated power valves) they are more inconsistent in their operation than Suzuki's mechanical method of activating the LT 250/500 exhaust valve.

If I were going to start with a clean sheet of paper, I would build a cylinder where the power valve was operated by a computer controlled stepper or servo motor.   The 125cc, 250cc, and 500cc GP racing engines used the servo/stepper motor actuated power valves and was very successful for many years.   The 500cc GP engines made in excess of 200 HP on gas and had a power band like a 4 stroke.   

If we add this type of power valve technology to our new cylinder, now the $1000.00 to $1500.00 cylinder kit cost is around $2500.00.