Most transformative mod you've done on your car, for better or worse?

Posted by mymomisyourfather@reddit | cars | View on Reddit | 214 comments

Curious; for those who've done mods to their current car or modded their past cars;

which mods did truly transform your car? can be in a positive or negative way For me;

Positive mod: A transmission mount insert in the B9 Audi platform has zero downsides but made the shifting and downshifts especially so much smoother. For me it transformed the car for such a small sum.

Negative mod: On an old Alfa I changed the engine mounts to polyurethane believing it to be an upgrade over stock. Rattled my fillings loose and made the car unbearable. When I changed it back to OEM a year later it was like owning a different car again