Originally Posted by Arben72
Well your other choice is 3m double sided tape. If you do your spoilers in that they will probably fly off at high speeds. The mirror caps clip in so no worry on those.
^This is not true.
I have taken my car (CF splitters, spoiler, diffuser) well over 130mph on a track with no problem. A full track day (~10 sessions) and no sign of wiggle. 3M is just fine for keeping parts on a car at high speeds. It's the imitators of 3M you need to worry about.