Akrapovic 991.2 GT3 RS Exhaust: 2018 Titanium Guide

The right Akrapovic 991.2 GT3 RS exhaust does not chase volume for its own sake — it answers a 4.0-liter naturally aspirated flat-six that already revs to 9,000 rpm and makes one of the great factory soundtracks of the modern era. This guide covers every Akrapovic system we stock for the second-generation 991.2 cars: the 2018–2019 Porsche 911 GT3 (and GT3 Touring) and the 2018–2020 Porsche 911 GT3 RS, all powered by the race-derived 4.0L motorsport engine. From the flagship Slip-On Race Line with a carbon fiber diffuser to the standalone titanium Tail Pipe Sets, here is what fits, what it changes, and how to specify it correctly.

What Akrapovic offers for the 991.2 GT3 & GT3 RS

Akrapovic builds a deliberately modular range for the 991.2 chassis, so you can buy the level of transformation you want. At the core is the Slip-On Race Line in titanium, available for both the GT3 and the GT3 RS. It bolts onto the factory system as the first step in the tuning ladder, replacing the rear muffler section with a hand-welded titanium unit. From there, Akrapovic offers it in several configurations: complete with carbon tips and a carbon fiber rear diffuser, complete with a titanium Tail Pipe Set, with titanium tips, or as a base muffler that requires a separate Tail Pipe Set to finish it.

Below the full systems sit the standalone Tail Pipe Sets in titanium for both the GT3 and GT3 RS — the visible, hand-finished outlets that complete a Race Line muffler or refresh a worn factory tip. There is also a high-gloss carbon fiber rear diffuser sold separately for the GT3 RS. Every piece is engineered around the 991.2’s rear-engine packaging and the GT3 program’s standards.

The flagship: Slip-On Race Line — material, tips, construction

Akrapovic’s Slip-On Race Line is the entry point of the system, but on a GT3 it is anything but ordinary. The muffler is built from hi-grade titanium, hand-welded, and engineered to install directly onto the Porsche’s original system — no headers or catalytic-converter surgery required. That makes it the most accessible route to the Akrapovic character: lighter weight, a freer-flowing rear section, and the distinctive twin double-round tailpipe signature the brand is known for.

On the GT3, the headline configuration is the Slip-On Race Line in titanium with carbon tips and the high-gloss carbon fiber rear diffuser. It is the most visually complete package, finishing the rear of the car with hand-laid carbon as well as the titanium outlets. If you prefer an all-metal look, the same Race Line is offered with a full titanium Tail Pipe Set or with titanium tips. There is also a base muffler sold without a Tail Pipe Set for buyers who already own the outlets or want to specify them separately — that version requires a Tail Pipe Set to be road-presentable.

Tail Pipe Sets & tips

The Tail Pipe Set is the part of an Akrapovic system you actually see, and Akrapovic offers it as a standalone titanium component for both the GT3 and the GT3 RS. These hand-finished outlets pair with the Race Line muffler to complete the look, and they are also the correct way to specify the rear of the car when you order a base muffler. On the 991.2, the configuration matters: when you combine the slip-on system with the carbon fiber diffuser, Akrapovic mandates a specific Tail Pipe Set, so it is important to match the outlets to your chosen muffler and diffuser combination rather than mixing parts at random.

For owners who already run a compatible muffler and simply want the genuine titanium look, the standalone Tail Pipe Sets are the cleanest upgrade in the range. At NLP Performance we keep both the GT3 and GT3 RS sets in stock.

Slip-On Line vs Evolution vs Race Line

Akrapovic structures its catalog into tiers, and understanding them helps you specify correctly. The Slip-On Line is the bolt-on entry point: it swaps the rear muffler section and delivers the lighter weight, freer flow, and signature sound with the simplest installation. The Evolution Line goes further, replacing a much larger portion of the system — including headers and link pipes — in full titanium for the most dramatic result. The Race Line shares the Evolution’s flow-focused design philosophy and uncompromising performance intent; the distinction Akrapovic draws is that Evolution components are built entirely in titanium where comparable Race-tier hardware can use stainless steel in the header section, with performance kept on par.

For the 991.2 GT3 and GT3 RS, the systems we stock are Slip-On Race Line mufflers, which can later be upgraded into a fuller Evolution-style setup by adding the appropriate header and link-pipe hardware. Start with the slip-on, then build up if you decide to chase the maximum.

Weight savings & materials

Titanium is the whole story here. Akrapovic builds these mufflers and tail pipes from hi-grade titanium, which is dramatically lighter than the steel it replaces and resists the heat and corrosion a track-day GT3 throws at it. For the 991.2 Slip-On Race Line, Akrapovic publishes a weight saving of roughly 1.1 kg (about 2.4 lb) over the stock rear section — modest in isolation, but it is removed from the very back of the car, exactly where Porsche’s own GT engineers obsess over reducing mass. Add the carbon fiber rear diffuser and tips and the gains compound, both on the scale and visually.

The carbon work is hand-laid and offered in a high-gloss finish, designed to integrate with the titanium outlets. It is the kind of detail that separates a genuine factory-partner system from a generic aftermarket muffler.

Sound & performance: what to expect

The 991.2’s 4.0-liter naturally aspirated flat-six produces 500 horsepower in the GT3 (more in the RS), spins to a 9,000 rpm redline, and was derived directly from the 911 GT3 Cup race car. An Akrapovic slip-on does not try to reinvent that engine’s character — it sharpens it. Expect a cleaner, more metallic top end, a harder edge as the tach sweeps toward 9,000, and the unmistakable Akrapovic timbre under load, all without the drone that plagues cheaper systems.

On the performance side, Akrapovic’s published figures for this platform show small but real gains from the reduced backpressure and lighter rear section — on the order of a few kilowatts and a few newton-metres high in the rev range, where this engine lives. The honest takeaway: buy an Akrapovic 991.2 system for the sound, the titanium weight savings, and the carbon-and-titanium aesthetics, with the modest power and breathing improvements as a welcome bonus rather than the headline.

Fitment: exact years, engine code, and variants

The systems on this page are engineered for the 991.2 generation and its 4.0-liter motorsport flat-six. The GT3-specific Slip-On Race Line configurations and the GT3 Tail Pipe Set fit the 2018–2019 Porsche 911 GT3 (and the GT3 Touring, which shares the powertrain). The GT3 RS hardware — the RS Slip-On Race Line with titanium tips, the RS Tail Pipe Sets, and the high-gloss carbon diffuser — fits the 2018–2020 Porsche 911 GT3 RS (991.2). The flagship Slip-On Race Line with carbon diffuser is cataloged across both the GT3 and the GT3 RS for the generation.

Because Akrapovic ties specific Tail Pipe Sets to specific muffler and diffuser combinations on the 991.2, always confirm your exact car (GT3 versus GT3 RS) and your chosen configuration before ordering. If you are running the carbon diffuser, the outlet you need is dictated by Akrapovic’s fitment notes for that combination.

Installation & what’s required

As a slip-on, the Race Line muffler is engineered to bolt onto the factory system, which keeps installation relatively straightforward for a shop familiar with the 991.2. There are no header or catalytic-converter modifications involved at the slip-on stage. The critical detail is specifying tips correctly: the GT3 RS base Slip-On Line is listed as requiring tips, and the carbon-diffuser flagship has a mandated Tail Pipe Set. In practice that means you should not order a bare muffler expecting a complete, finished rear — confirm whether your chosen system includes tips or needs a matching Tail Pipe Set added to the order.

At NLP Performance in Tampa, FL, we help GT3 and GT3 RS owners spec the exact Akrapovic combination for their car so the muffler, tips, and diffuser all match Akrapovic’s fitment guidance the first time. Given the value of these systems — and the cars they go on — we recommend professional installation by a Porsche-experienced technician.