Exhaust› Mufflers and Resonators

Grail

Valved Rear Muffler System

$4,916.00

SKU: GR-21CAYMANGT4

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In Stock
Ships by Aug 1
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30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

The Grail GR-21CAYMANGT4 is an ECE-approved valved exhaust system specifically engineered for the Porsche 718 Cayman GT4. This system includes a valved rear muffler and offers the option of dual tailpipes. The valved design allows for adjustable sound profiles, providing a sharper sound when desired. According to available information, Grail exhaust systems for the Porsche 718 Cayman GT4 are approximately 3kg lighter than the OEM system, and the OPFs (Otto Particulate Filters) remain installed, ensuring compliance and emissions standards are met. Installation instructions are typically not included, and professional installation may be recommended.

MIA's Description

The Grail GR-21CAYMANGT4 is a valved rear muffler system designed for the Porsche 718 Cayman GT4. This exhaust system features ECE approval, ensuring it can be used on EU vehicles without registration. It includes dual or optional none tailpipes.

Fitment

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Specifications

BrandGrail
Part NumberGR-21CAYMANGT4
CategoryExhaust

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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