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Porsche 718 Cayman GT4 RS (982) | Prepreg Dry Carbon Fiber Rear Diffuser
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- 24-Month BYC WarrantyIn addition to your legal rights
- ImportedOEM fit
Porsche 718 Cayman GT4 RS (982, 2022+) Prepreg Dry Carbon Fiber Rear Diffuser
Engineered for Porsche 718 Cayman GT4 RS (982 chassis, 2022+) owners, this Prepreg Dry Carbon Fiber Rear Diffuser brings race-grade carbon finish to the motorsport DNA of the 500 hp 4.0L flat-6 naturally-aspirated GT4 RS. Imported from leading manufacturers around the world and quality-controlled by BYC Performance, this Porsche GT4 RS carbon rear diffuser bolts directly to GT4 RS-specific rear bumper mounting points - no cutting required.
The 718 Cayman GT4 RS produces 500 hp from a 4.0L flat-6 naturally-aspirated engine inherited from the 991.2 GT3; it is the most aggressive Cayman-bodied Porsche, sold only as a Coupe. This dry carbon rear diffuser completes the GT4 RS motorsport aero package; noticeably lighter than the factory plastic part, far stronger, and outstandingly UV-resistant. Autoclave-cured prepreg carbon is the production method widely chosen in motorsport.
Key Features
- Prepreg (Dry) Carbon Technology: Autoclave-cured under high heat and pressure; homogeneous resin, a more consistent weave.
- GT4 RS-Specific Geometry: Diffuser profile designed specifically for the GT4 RS wide and aggressive rear bumper aero lines.
- Motorsport DNA: Deep channel geometry aligned with the 4.0L flat-6 (inherited from 991.2 GT3) track character.
- Weight Reduction: Noticeably lighter than the factory plastic part; reduces non-rotational mass at the rear axle.
- 2x2 Twill Carbon Weave: Authentic carbon pattern under a high-gloss UV-protective clear coat.
- Direct OEM Fit: Plug and play installation on the 718 Cayman GT4 RS rear bumper mounting points.
- UV and Chemical Protection: Long-life clear coat protects against fading, cracking, and exhaust heat.
Prepreg (Dry) Carbon vs. Wet Carbon - Which Is Better?
Most aftermarket carbon parts are made using wet lay-up, where resin is applied by hand and cured at room temperature - leaving air voids and inconsistent weight. Prepreg (dry) carbon:
- Cured in an autoclave under high heat and pressure - a more consistent weave
- A controlled resin ratio - lighter and stronger
- The production method widely chosen in motorsport
- Minimal UV fading over years of use
Installation Notes
Installing the Porsche GT4 RS carbon diffuser is a direct replacement of the factory part. Professional installation is recommended:
- Raise the vehicle and remove rear bumper underbody screws.
- Carefully detach the OEM GT4 RS diffuser from clips and bolts.
- Test-fit the carbon diffuser for alignment.
- Secure with supplied hardware to the manufacturer's recommended torque.
- Verify the GT4 RS twin center-exit exhaust tips are centered in diffuser cutouts.
Care and Maintenance
Wash with pH-neutral car shampoo. Apply carbon-safe sealant every 6 months. Keep pressure washer nozzle at least 30 cm from surface. Avoid sudden cooling of a hot diffuser surface after track use.
FAQ
Does this fit the standard 718 Cayman?
No. This part only fits the 718 Cayman GT4 RS (2022+) rear bumper geometry. A separate carbon rear diffuser for the standard Cayman/Boxster is available in our catalog.
Does this fit the Cayman GT4 (4.0, 2020+)?
No. The standard Cayman GT4 and GT4 RS rear bumpers differ. The GT4 RS rear bumper has motorsport-specific widened aero.
Is there a Boxster Spyder or Boxster GT4 RS?
No Boxster GT4 RS exists. This part is only for the Cayman GT4 RS Coupe.
Does this fit the 981?
No. The 981 (2013-2016) and 982 have different rear bumper geometry.
Is it track-rated?
Yes. Autoclave-cured prepreg carbon withstands track temperatures and vibration; designed with the GT4 RS track usage profile in mind.
Will rain damage dry carbon parts?
No. Autoclave-cured prepreg carbon is fully waterproof.
Shipping time?
In-stock items ship within 1-3 business days. Parts sourced to order are delivered within 30 days of the order date at the latest.
Warranty?
Manufacturing defects are covered by a 24-month BYC warranty, in addition to your legal rights.
Why BYC Performance?
BYC Performance is a Turkey-based performance tuning specialist sourcing premium carbon fiber parts from leading manufacturers around the world and supplying them to the Turkish market. Our catalog includes Porsche carbon parts, Porsche 911 GT3 RS carbon spoilers, Audi R8 carbon diffusers, BMW M3 carbon diffusers, and many more high-quality carbon components. All parts undergo strict quality control.
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