Will this diffuser scrape on steep driveways or inclines?

The diffuser extends the rear bumper line downward. Before installation, measure the OEM bumper's lowest point and compare it to your typical driveway approach angles and speed bump heights. This ensures clearance matches your driving environment. If ground clearance is marginal, consider your local terrain before committing to install.

Does this diffuser provide functional downforce or is it cosmetic?

L Sport diffusers are primarily visual upgrades that enhance the aggressive styling of the rear end. While the shape mimics performance diffuser geometry, real downforce benefit depends on vehicle speed, aerodynamic integration with the rest of the body, and CFD tuning—factors beyond this single component. Install it for the look; any performance gain will be minimal at street speeds.

What finish should I apply to the carbon fiber?

Sand and prep the surface before applying your chosen finish. Many owners apply a UV-protective clear coat to preserve the weave pattern and protect against UV damage over time. Others leave it raw for an unfinished carbon look. The choice depends on your aesthetic preference and climate exposure.