Will this scrape on speed bumps or steep driveways?

The Gran Veloce diffuser follows the factory rear bumper line, so clearance mirrors your stock setup. If you run lowered suspension, you'll want to verify ground clearance at your typical approach angles before committing—same due diligence you'd do with any rear aero.

Is this functional downforce or purely cosmetic?

This is styling-focused. It sharpens the rear aesthetic with aggressive lines and depth, but aerodynamic benefit depends on vehicle speed and overall aero package integration. It's built to look right without compromising underbody flow.

What prep work should I do before installation?

Ensure the rear bumper surface is clean and free of wax or residue where the diffuser mounts. Dry fit first to confirm fitment against your bumper profile, then follow your fastener schedule. Carbon fiber can be sensitive to point loads, so distribute clamp pressure evenly during tightening.