Description
NOTE: Includes both a rear diffuser and rear under spoiler. Since these products are molded by the manufacturer, cutting may be required for vehicles equipped with non-standard mufflers. Drilling is required to secure the bolts and nuts for installation. FRP components are unpainted.
Note: The J's Racing Under Spoiler comes standard as FRP with no option for CFRP. The J's Racing Rear Diffuser can be ordered in either FRP or CFRP.
Rear Diffuser with FRP Under Spoiler
Transform the rear view and performance of your vehicle with a powerful rear under aero package engineered to enhance airflow and stability. The aggressively upswept shape is optimized to improve rear air flow, while a wide center rear duct reduces the parachute effect created by air entering around the muffler—cutting drag and resistance. Designed as a replacement for the genuine under spoiler, it mounts directly using the factory bumper body for a clean, precise fit. Pairing the under spoiler with the diffuser delivers a more commanding rear profile and further improves aerodynamic efficiency.
Beyond style, this setup increases streamlining and downforce for more confident high-speed stability. An available carbon construction utilizes vacuum infusion molding to minimize resin irregularities and air bubbles compared to conventional methods, delivering high strength with reduced weight.
*Items shown in some images may be painted or clear-coated for display. FRP arrives unpainted; carbon variants may require polishing and UV-resistant clear coating for a glossy finish.