MX-3.com

I hit 237 in my black GS. I was hitting 7600rpm in 5th, almost fuel cut. You cannot go over 240 with a mx3 trans. MX6 tranny maybe 250-255

You'd need over 400WHP to hit 300kmph. That would be with an upgraded valve train and physically pushing the gearbox to higher than 7500rpm to forcefully get past the speed limit of our gearboxes @ 7500rpm. You most likely need cams that make power in much higher revs too. Potentially race cams that wouldn't even be good on the street.