Will this interfere with my trunk seal or bumper gaps?

This front lip mounts to the lower fascia, not the trunk area. Verify your bumper's factory mounting holes align with this design before installation. If you've modified the lower bumper section, test fitment first.

Does the carbon fiber need any prep before installation?

The clear coat is factory-applied. Before mounting, clean both the bumper attachment points and the lip's mounting surface with rubbing alcohol and let dry completely. Sand the mounting contact areas lightly to ensure a secure bond.

Will this lip stay stable at highway speeds?

The single-piece design is rigid carbon fiber and mounts directly to the OEM bumper structure. Secure all fastening points firmly—refer to your vehicle's service manual for proper torque specs on existing bumper hardware—and it will remain stable through normal driving.