I'm considering investing in a K&amp;N replacement filter for my Passat (which is about the only tuning mod available!), but afriend has told me the car should be rolling-roaded afterwards?</P>


Not heard this before, but he knows more about tuning than I'll ever know! Any advise would be appreciated.</P>


Stu.</P>

 

a rolling road is when your car is put a rolling set of bars and driven(so it doesnt actually go anywhere.)by doing this you can work out the brake horse power and other statistics about pick up and stuff.The reason for this would be because the air filter will make your car a little more responsive and maybe a little more powerful, but not that much. if you really want to know the exact change the air filter has made then do it, but you could just look in your manual and add 5-10 horse power.