Will this diffuser scrape on driveway aprons or steep inclines?

Diffuser ground clearance depends on your suspension setup and ride height. Measure the distance from your current bumper line to the ground, then verify the installed depth of this three-piece assembly against your vehicle's undercarriage. Lowered setups will have less margin than stock geometry.

Is this functional downforce or cosmetic styling?

This Weaver style diffuser is primarily a visual upgrade that mimics aggressive aerodynamic design. Real downforce requires a complete aero package engineered with computational fluid dynamics. Use this piece for the look you want without expecting measurable track performance gains.

What prep work does the carbon fiber need before installation?

Sand and prep the mounting surface on your bumper to remove any loose material or debris. The diffuser arrives finished with clear coat, so no additional painting or sealing is required. Follow your vehicle's service manual for fastener torque values when securing the assembly.