Fabspeed High-Flow Catalytic Downpipe for Porsche 718 Boxster & Cayman (2017–2024)

Description

The Fabspeed Sport Cat with Downpipe replaces the restrictive factory catalytic converter and downpipe on 2017+ 718 Boxster / Cayman with a high-flow, performance-oriented stainless system. Using one of the largest, OEM-fit high-flow catalytic converters available (German-made HJS), and mandrel-bent stainless tubing, this upgrade improves exhaust flow and throttle response — while retaining emissions compliance and avoiding check-engine issues. The result: a richer, deeper boxer-engine rumble, sharper turbo response, and a noticeable gain in mid-range power and overall drivability.

Fitment Notes

• Designed for Porsche 718 Boxster / 718 Cayman models from 2017 onward (Base, S, GTS, and applicable trims). 

• Direct bolt-on replacement for the stock catalytic converter and downpipe — uses factory mounting points. 

• Because it uses a compliant high-flow catalytic converter, the setup maintains emissions filtering and is engineered to avoid triggering check-engine lights under normal operation.

Included

• High-flow catalytic converter (HJS 200-cell EURO 6 trimetal catalytic converter) sized to maximize flow while fitting in stock location.

• Mandrel-bent T304L stainless steel downpipe section (primary 3″ tubing transitioning to dual 2″ outlets) for optimal flow and fitment. 

• All required mounting hardware, flanges, and gaskets for a clean bolt-on installation (no cutting or fabrication needed).

Product Specs

• Catalytic Converter Type: HJS 200-cell trimetallic catalytic converter — high-flow, emissions-compliant, largest fitment possible for the 718 chassis. 

• Pipe Material: T304L stainless steel, mandrel-bent for smooth internal flow and durability. 

• Primary Tube Diameter: 3.0 inches (≈ 76 mm) — maximizes exhaust flow from turbo/downpipe junction. 

• Outlet Configuration: Transition to dual 2.0-inch pipes continuing into stock or aftermarket exhaust downstream. 

• Estimated Power Gain (stock exhaust downstream): ~ +20 wheel horsepower (whp) across the RPM band compared to factory downpipe.

• Exhaust Sound / Character: More pronounced boxer-engine rumble with deeper tone and enhanced turbo burble under load — with no excessive drone in normal driving. 

• Fitment: Direct bolt-on — designed for factory turbo layout and exhaust routing, with no modifications needed. 

• Warranty / Build Quality: Built with hand-welded stainless steel components; installation hardware included; backed by Fabspeed’s warranty program.

Product Features

• High-Flow Catalytic Converter for Compliance + Performance — The HJS high-flow cat delivers exhaust flow close to that of a straight pipe while maintaining emissions filtering and avoiding check-engine lights.

• Improved Turbo Spool & Throttle Response — Reduced back-pressure accelerates turbo spool-up and delivers sharper throttle response and mid-range punch — noticeable in everyday driving and spirited acceleration.

• Enhanced Exhaust Note without Excessive Drone — Deepened boxer exhaust tone with stronger burbles and pops on throttle and shift, while staying manageable for street use.

• Bolt-On, OEM-Friendly Installation — No cutting, welding, or custom fabrication required — makes this an easy garage or shop install with factory mount points.

• Durable, Corrosion-Resistant Construction — Stainless-steel tubing and quality welding ensure longevity even under aggressive driving or occasional track use.

• Solid Base for Future Mods — With improved exhaust flow and minimal restriction, this downpipe/cat setup creates a strong foundation for further upgrades (intake, tune, full exhaust) for bigger gains.

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