I have several mates who regularly pull 200 plus kph on the race track the main prob is air under the front wheels and air flow off the rear end of the beetle,in standard form the Bug cant deal with this so the only options that work are Kamei front air dams and good porsche style rear wings,they do change the look of the good old bug but if you want to go f...ing fast you have to make some sacrifices,we also have things called Aero Guards down under that are wider and lower at the front edge to stop air getting under the wheels these work better than a Kamei and look better also.they also stop air flow under rear arches also stopping tail float,if you incorperate a rear wing your bug will stick like dog **** to your shoe! check out
www.beetleracing.com they can supply Aero guards and have a neat GT3 style wing that gives greate down force and extra air flow to engine bay,they also look good and actualy work!