Quote Originally Posted by Mk6 GTI View Post
Hi All,

Are there performance improvements i can make to the GTI that will still be covered under warranty?

Cheers!
Better tyres & lightweight quality rims are a performance enhancement that should not affect warranty.

Just about anything else (suspension improvements, remaps, etc) give VW an opening to negate warranty on related items. eg: a remapped ECU won't affect the warranty on the windscreen wiper motor.