Next Level Performance
September 4, 2026 • 11 min read
Our Verdict
The aFe Gemini XV 304 stainless cat-back is our top pick for the 2018-2023 Kia Stinger GT 3.3T because its built-in exhaust cut-out gives you a quiet commute and a wide-open snarl from the same system.
All five kits here bolt to the 365-horsepower twin-turbo V6, drop 15 to 25 pounds of factory weight, and skip the drone traps of a cheap universal muffler. Your choice comes down to sound character, material, and budget — and we break down exactly where each one wins below.
Shop Our Top Pick →A Kia Stinger GT cat-back exhaust is the single most satisfying bolt-on you can add to the 3.3L twin-turbo V6, unlocking the deeper, harder-edged voice that Kia's factory muffler quietly smothers. The Stinger GT makes a genuine 365 hp and 376 lb-ft, yet leaves the showroom sounding closer to a luxury sedan than the fastback grand tourer it is. Swapping the restrictive OEM cat-back for a mandrel-bent stainless system wakes up that Lambda II V6, shaves real weight off the rear axle, and — on valved kits — lets you flip between stealth mode and full aggression on demand. At NLP Performance in Tampa, FL, the Stinger is one of the most common cars on our lift for exhaust work, so we pulled the five best cat-backs we stock and ranked them by sound, build quality, fitment, and value.
Why upgrade the Kia Stinger GT 3.3T exhaust?
A cat-back exhaust on the Stinger GT is primarily a sound-and-weight upgrade, not a big power mod — expect roughly 5 to 12 wheel horsepower on a stock tune, with the real dyno gains reserved for downpipes and a tune. The 3.3L twin-turbo V6 already flows well behind its turbochargers, so the restriction a cat-back removes lives in the muffler and resonators, not the mid-pipe. What you do get is dramatic: a 15 to 25 pound weight reduction versus the heavy factory valved muffler assembly, a noticeably deeper idle and mid-range, and the elimination of the piped-in quietness that makes a stock Stinger GT feel muted.
Pipe diameter matters more than most buyers think. On a 365 hp turbo V6, a 2.25in to 2.5in dual system keeps exhaust-gas velocity high for strong low-end torque, which is why every kit on this list stays in that window rather than jumping to a lazy 3-inch pipe that can soften throttle response. Material is the other long-term decision: 304 stainless steel resists corrosion and road-salt pitting, while budget aluminized steel will surface-rust over the years but saves you hundreds up front.
The aFe Gemini XV pairs 304 stainless mandrel bends with an electronic cut-out for on-demand volume.
How we picked these five cat-backs
We ranked every kit on four things a Stinger owner actually feels: material quality, sound character, fitment accuracy, and price-to-value. Each system here is a confirmed fit for the 3.3L twin-turbo V6 in both RWD and AWD trims, uses mandrel-bent tubing for uninterrupted flow, and comes from a brand with a real warranty behind it. We deliberately included a valved option, a couple of loud-and-proud fixed systems, an OE-sleeper choice, and a genuine budget pick so there is a right answer whether you daily-drive your Stinger or park it at cars-and-coffee.
| Kit | Material | Sound | Best For | Price |
|---|---|---|---|---|
| aFe Gemini XV (w/ Cut-Out)Top Pick | 304 Stainless | Adjustable (valved) | Quiet daily to full aggression | $2,347.00 |
| MBRP T304 Quad Outlet | T304 Stainless | Aggressive | 2022+ facelift & quad tips | $2,084.99 |
| MagnaFlow (Reuse Fascia Tips) | 304 Stainless | Moderate | OE-look sleeper build | $2,064.00 |
| Borla S-Type | T-304 Stainless | Aggressive | Proven brand & warranty | $1,699.99 |
| MBRP Aluminized (No Tips) | Aluminized Steel | Bold | Budget builds | $889.99 |
The 5 best Kia Stinger GT cat-back exhausts
1. aFe Gemini XV 304 SS Cat-Back w/ Cut-Out — Best Overall
The aFe Gemini XV is the most versatile Stinger GT cat-back you can buy because its integrated electronic cut-out lets one system be both a quiet cruiser and an open-valve monster. Built from 2.5-inch mandrel-bent 304 stainless, it keeps mid-range velocity strong on the 3.3T while the valve, closed, tames drone for long highway pulls — then opens for a raw, race-adjacent bark under boost. It is the priciest kit here, but it is genuinely two exhausts in one.
Key Specifications
What We Like
- + Electronic cut-out switches between quiet daily and full-open aggression
- + Mandrel-bent 304 stainless resists rust in humid Florida climates
- + 2.5in dual path preserves 3.3T mid-range torque while adding volume
Things to Consider
- – Highest price of the five kits
- – Cut-out valve adds wiring and install steps over a fixed cat-back
2. MBRP T304 Quad Outlet — Best for 2022+ Facelift Stingers
The MBRP T304 cat-back is the smart pick for 2022-and-newer Stinger GTs because it is engineered around the facelift car's quad-tip rear bumper and reuses the factory bezels for a seamless OEM-plus look. Fabricated from corrosion-resistant T304 stainless with dual split-rear routing, it delivers an aggressive tone that stays civil enough for daily driving, and it carries MBRP's limited lifetime warranty against defects. At just over $2,000 it undercuts the valved aFe while still using premium stainless.
MBRP's quad-outlet routing reuses the factory bezels for a clean OEM-plus rear on 2022+ cars.
3. MagnaFlow 304 SS — Best OE-Look Sleeper
The MagnaFlow cat-back is the sleeper's choice because it reuses the Stinger's factory fascia exhaust tips, so the car looks bone-stock while sounding anything but. Built from 304 stainless and backed by MagnaFlow's lifetime warranty, it delivers a refined, moderate-volume tone that adds depth without the cabin drone that turns a fun highway trip into a headache. For owners who want more voice but no visual giveaway — or who plan to keep the OE quad tips on a facelift bumper — this is the pick.
4. Borla S-Type — Best Proven Brand & Warranty
The Borla S-Type is the enthusiast default for the 2018-2021 Stinger GT because it pairs Borla's aggressive-but-livable signature tone with a patented, run-what-you-brung Million Mile Warranty. Its 2.25-inch T-304 stainless tubing and dual split-rear exit keep exhaust velocity high for crisp throttle response, and the S-Type muffler tuning lands squarely between the mellow Touring line and the raucous ATAK. If you want a decades-proven name that will outlast the car, this is it — and at under $1,700 it is the value sweet spot among the stainless kits.
Borla's S-Type muffler splits the difference between the mellow Touring and the raucous ATAK.
5. MBRP Aluminized (No Tips) — Best Budget Pick
The MBRP aluminized cat-back is the best budget path to a louder Stinger GT, delivering a bold, deep note for well under half the price of the premium stainless kits. Its 2.5-inch mandrel-bent tubing and dual rear-exit routing come without tips so you keep your factory fascia bezels, and the aluminized-steel construction is what keeps the cost near $900. Yes, aluminized steel will surface-rust over years of Florida rain versus 304 stainless, but for a bold sound-and-weight upgrade on a budget it is unbeatable value.
Sound, drone and daily drivability
Turbochargers act as mufflers, so even the loudest Stinger GT cat-back is more refined than a naturally aspirated V8, which makes the 3.3T an excellent candidate for an aggressive exhaust without unbearable cabin drone. The turbos scrub the harsh high-frequency rasp and leave a deep, boosty burble on lift-off. That said, drone at 70 mph cruise is the number-one complaint on any turbo-car cat-back, and it is exactly why our top pick uses a valve: with the aFe Gemini XV cut-out closed, highway resonance drops to near-stock levels. Fixed systems like the Borla S-Type and MBRP T304 manage drone well through chambered muffler tuning, while the MagnaFlow leans quietest of the group. Add a downpipe later and every one of these gets louder, so pick your baseline volume with headroom in mind.
Mandrel-bent stainless tubing keeps flow smooth from the mid-pipe back to the tips.
Installation and fitment notes
A Stinger GT cat-back is a bolt-on, direct-fit job that a competent DIYer can complete in about 1.5 to 2.5 hours with hand tools and a set of jack stands. Every kit here is a slip-and-clamp or flange-to-flange replacement that reuses OE hangers, and all five confirm fitment for both RWD and AWD 3.3L V6 cars. The single most important fitment detail is your rear bumper: pre-facelift 2018-2021 cars and the 2022+ facelift use different exhaust-tip cutouts, so match the kit to your year — the MBRP T304 quad-outlet and the tip-free options are built with that in mind. If you would rather not crawl under the car, our Tampa, FL shop installs and leak-checks any of these systems, and our fitment team can confirm the right part for your exact VIN before you order. Browse the full catalog in our exhaust systems collection to pair your cat-back with a downpipe or tune down the road.
Frequently Asked Questions
How much horsepower does a cat-back exhaust add to a Kia Stinger GT?
A cat-back exhaust adds roughly 5 to 12 wheel horsepower to a Kia Stinger GT 3.3T on a stock tune. The bigger benefits are a 15 to 25 pound weight reduction and a much deeper exhaust note. To unlock serious power on the twin-turbo V6, you need downpipes and an ECU tune, which the cat-back complements rather than replaces.
Will a Stinger GT cat-back exhaust cause drone?
Some highway drone is possible, but the Stinger GT's turbochargers muffle much of the harsh resonance, so a well-tuned cat-back stays livable. Valved systems like the aFe Gemini XV eliminate drone entirely with the cut-out closed, and chambered fixed systems such as the Borla S-Type and MagnaFlow keep cruise resonance to a minimum.
Do these exhausts fit both RWD and AWD Kia Stinger GTs?
Yes. All five cat-back systems in this guide fit both rear-wheel-drive and all-wheel-drive 3.3L twin-turbo Kia Stinger GT models. The exhaust routing sits behind the transmission and is unaffected by the drivetrain, so the only fitment variable that matters is your model year and rear bumper tip style.
Is 304 stainless steel worth it over aluminized steel?
For long-term durability, yes — 304 stainless steel resists rust and road-salt corrosion for the life of the car, while aluminized steel will surface-rust over several years. If you keep your Stinger long-term or drive in wet or salted climates, choose a 304 kit like the aFe, Borla, MBRP T304, or MagnaFlow. The aluminized MBRP is the right call only when budget is the priority.
How long does it take to install a Kia Stinger cat-back exhaust?
Most enthusiasts install a Stinger GT cat-back in 1.5 to 2.5 hours using jack stands and basic hand tools. Each kit is a direct-fit, bolt-on replacement that reuses the factory exhaust hangers. If you prefer professional installation, NLP Performance in Tampa, FL fits and leak-checks any of these systems.
Which Kia Stinger GT cat-back exhaust is the best?
The aFe Gemini XV with cut-out is the best overall Kia Stinger GT cat-back exhaust because its electronic valve delivers both quiet daily driving and full-open aggression from one 304 stainless system. Budget shoppers should choose the MBRP aluminized kit, while 2022+ facelift owners get the cleanest fit from the MBRP T304 quad-outlet system.
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