Will this scrape on steep driveways or inclines?

The SRK profile sits lower than OEM bumpers. Before installation, check your vehicle's ground clearance at the steepest angles you encounter regularly. If you frequently navigate sharp inclines, verify the diffuser tip clearance against your driveway slope or consider approach angle on parking lot entries.

Is the diffuser purely cosmetic or does it add functional downforce?

This is a styling piece designed to match the aggressive SRK aesthetic. Real-world downforce benefit at street speeds is minimal with a rear diffuser alone; aero gains typically require a complete package (splitter, side skirts, wing). Use it as the visual anchor to your rear-end styling.

How should I prep the surface before installation?

Sand and prep the mounting surface on your bumper to ensure clean contact. Carbon fiber benefits from a protective clear coat finish to guard the weave against UV and minor abrasion — apply your chosen automotive clear before final fitment if you want maximum durability.