Will this lip interfere with my front bumper undertray or splash shield?

No. This lip mounts to the bumper's top edge and factory attachment points. Before installation, verify your vehicle's OEM undertray configuration to ensure the splitter sits clear of any trim or ducting. Minor fastener repositioning may be necessary depending on aftermarket bumper modifications.

Should I apply clear coat before installing, or after?

Apply clear coat before installation. This protects the weave pattern from UV exposure and road debris. Once cured, proceed with mounting. If you prefer color-matched finish, sand and prep the surface, then apply your chosen base coat and clear coat before fastening to the bumper.

How stable is a carbon lip at highway speeds?

Carbon fiber is stiffer than OEM plastic and resists flex. This lip's single-piece construction and factory bolt points provide solid stability at highway velocity. Ensure all fasteners are tight before driving, and periodically check mounting bolts during the first 500 miles for any settling.