First of all I would say.....is it proper working condition? Meaning, fresh top end, proper jetting ect. If it is and you still want more power then first put on a k27 FMF fatty moto pipe. (make sure it's a k27) This adds a lot of power through out the powerband. Second, have the head milled .020. Third, have the cylinder ported by a reputable company or person. If you do all this and it is done right, the bike will fly. I actually modified the 94 cylinder to accept the bigger 98 power valve on mine and got even more power. It was so fast that it would out accellerate my brothers KTM 520 sx! :smile:bonehead said:i have a stock 1994 kx 250 engine & im using it for drag race, i need help, what modifications do i need to make this engine run more faster? thanks