Best valved exhaust for BMW M340i G20 / G21 and M440i G22 / G23
BMW M340i saloon G20 or Touring G21, M440i coupé G22 or convertible G23: for these four cars, we recommend a valved cat-back made from the VIN, which frees the song of the B58 six-cylinder without taking away its manners as a big tourer. Each model has its Rog product page; this guide describes the two cars and their shared engine, then the configurations we advise for them.
Your valved exhaust for BMW M340i B58 G20 / G21 is configured from your VIN, and the BMW 3 Series G20 / G21 Valved Exhaust page brings together every system we make for this generation.
Your Rog exhaust: BMW M340i G20 / G21 and M440i G22 / G23
Configure my exhaust- Vehicles
- M340i saloon G20 and Touring G21 since 2019; M440i coupé G22 and convertible G23 since 2020
- Engine
- B58, 3.0-litre six-cylinder, twin-scroll turbo
- Exhaust
- Valved cat-back, one product page per model
- Sound
- Straight pipe, or resonator at the same price
- Material
- 304 stainless steel; brushed, gold or purple titanium
- Front section
- B58 downpipe, with or without catalytic converter, as an option
- Valves
- The valve of your BMW or the Rog remote
- Lead time and warranty
- 20 working days of manufacture, free delivery, 3-year warranty
Your vehicle.
All our exhausts for these two generations, version by version, are brought together on two pages: BMW 3 Series G20 / G21 Valved Exhaust and BMW 4 Series G22 / G23 / G26 Valved Exhaust.
The M340i and the M440i are the two six-cylinder sports models of the current 3 Series and 4 Series. They share the same B58, the same gearbox and the same philosophy: plenty of performance, without giving up the comfort of an everyday car. Here is what brings them together, what sets them apart, and what that changes for your exhaust.
- M340i
- Saloon G20 and Touring G21, since 2019
- M440i
- Coupé G22 and convertible G23, since 2020; the Gran Coupé G26 has its own guide
- Engine
- B58: 3.0 litres for an inline six-cylinder, twin-scroll turbo, direct injection at 350 bar
- Factory output
- 374 hp (275 kW) and 500 Nm; 392 hp (288 kW) and 540 Nm on cars produced since late 2025
- Gearbox and drivetrain
- Eight-speed Steptronic Sport; xDrive as standard on European versions
- Differential
- M Sport differential with electronically controlled locking
- Factory exhaust
- M Sport exhaust, two trapezoidal outlets; electrically operated valve on the M340i
- Front section
- Downpipe at the turbo outlet, catalytic converter included
Two models, a single six-cylinder
BMW presented the 3 Series G20 in autumn 2018, and the M340i made its debut at the Los Angeles Auto Show in November of the same year. The Touring G21, its estate counterpart, followed in 2019. The M340i is the most powerful 3 Series below the M3: it takes the bodywork of the saloon or the family estate, with a sportier chassis setup and equipment.
The M440i is its coupé and convertible variant within the 4 Series. The G22 coupé was unveiled in June 2020 and went on sale in the autumn; the G23 convertible joined the range shortly afterwards. Both take the M340i's B58, tuned identically. The Gran Coupé G26, four doors and a hatchback, is treated separately, on a product page and in a guide devoted to it.
The bodies share the Rog product pages two by two: the saloon and the Touring on the M340i page, the coupé and the convertible on the M440i page. The M340i page also covers the 3 Series facelifted in 2022; in every case, your VIN confirms the right product page before manufacture.
374 hp, then 392 hp
At its launch, the M340i is quoted at 374 hp (275 kW) and 500 Nm, which is 48 hp and 50 Nm more than the most powerful 3 Series of the previous generation. According to BMW, the saloon takes 4.4 seconds to reach 100 km/h from a standstill, and the Touring 4.5 seconds. The M440i was launched with the same engine, combined with 48-volt mild hybrid.
For cars produced from November and December 2025, BMW raised the B58 to 392 hp (288 kW) and 540 Nm, 12 hp of which is supplied by the mild-hybrid system. This development concerns the M340i saloon and Touring as well as the M440i coupé, convertible and Gran Coupé. The Rog product pages cover both tunes, before and after that date.
Further down, two sets of bars, one for the M340i and the other for the M440i, show the figures of each product page.
BMW M340i B58 G20 / G21 3.0T, 374 hp (392 hp since 11/2025) factory
Power
Torque
BMW M440i B58 G22 / G23 3.0T, 374 hp (392 hp since 11/2025) factory
Power
Torque
Stage 2: published figures with the front section and an ECU remap carried out by a tuner.
xDrive, M Sport differential and eight-speed gearbox
In Europe, the M340i is delivered with the xDrive all-wheel drive, set up to favour the rear axle, and the eight-speed Steptronic Sport gearbox, with steering-wheel paddles and Launch Control. The M Sport differential, driven by an electric motor, can progressively lock the rear axle to get the torque down better on corner exit.
On the exhaust side, the Rog product pages reason by body style: one product page for the saloon and the Touring, another for the coupé and the convertible. The exact drivetrain and equipment of your car can be read from its VIN, which we check before manufacturing.
The B58 in detail
The B58 lines up six cylinders for 3.0 litres of displacement and gets by with a single twin-scroll turbo: its housing splits the gases into two flows, three cylinders each, as far as the turbine, which makes it respond earlier. For the M340i, BMW raised the injection pressure from 200 to 350 bar and cools the charge air with a water circuit. Peak torque arrives early and stays available over a wide band, which gives the characteristic continuous thrust.
This engine is also found in the 340i F30, the 540i G30 or the 840i G14: it is the six-cylinder BMW uses wherever it wants to combine flexibility and vigour. A single downpipe leaves the turbo outlet, carrying the catalytic converter: the front section. Then the cat-back begins, running under the floor to the rear bumper.
The song of the straight-six
An inline six-cylinder has a natural balance you can hear: no parasitic vibration, a linked sound that gains brilliance as the needle climbs. At idle, the B58 gives a round rumble; towards the top of the rev counter, the note becomes more metallic and tauter. It is a voice you would recognise among a thousand at BMW.
Once the Rog exhaust is in place and its valves open, this character takes its full place: a start-up that announces itself, rises in revs in one piece and clear crackles when you lift off the accelerator, especially when the gearbox downshifts in Sport mode. With the valves closed, the M340i becomes again the office saloon it can also be.
The standard valve and what holds the sound back
BMW fits the M340i as standard with an M Sport exhaust with a valve: in Sport or Sport Plus mode, the valve opens wider and the sound gets richer. The rest of the time, big silencers designed for the occupants' comfort and for noise regulations keep the six-cylinder at a distance. From outside, even in Sport Plus, the M340i gives away only a fraction of its engine's repertoire.
A valved exhaust changes this relationship without imposing anything. With the valves closed, the gases run through the silencer from end to end, and the M340i stays almost as composed as when it left the showroom, to leave its garage at six in the morning or to roll out a five-hundred-kilometre stage. With the valves open, they run straight through, and the six-cylinder is freed.
Factory valve or Rog remote
Both product pages leave you the choice. On an M440i, your VIN confirms the standard equipment to us before manufacture. With the Factory option, we prepare on the exhaust the mounting points for the BMW valves; your garage transfers those of your car there, and from Comfort to Sport Plus, the driving programmes keep control. With the Rog option, our valves are already in place on delivery, accompanied by a remote and a control unit to slip into the boot: the position you choose holds, whatever programme is engaged.
The first suits those who like the car to decide on its own according to the programme chosen. The second will please those who want a quiet Touring in Sport mode on the motorway, or a saloon that sings in Comfort mode on a Sunday morning.
What the product pages allow
On each product page, the cat-back comes in 304 stainless steel, robust, or in titanium, about 40% lighter for the same layout, whose brushed, gold or purple shade has no effect on the price. As for sound, the same pricing logic applies: straight pipe for the B58's raw grain, or resonator, which gives it a rounder and slightly softer voice, welcome in a family Touring or a cruising convertible.
The front section also appears on the product pages, on the "Manifold" line: a downpipe with a 200-cell sport catalytic converter, which preserves the B58's emissions control, a 100-cell version, accepted or not depending on the car and local regulations, or a catalyst-free version, reserved for the track. With the cat-back alone, the B58 keeps its ECU and its power; more horsepower requires the downpipe and a remap entrusted to a tuner.
Rog makes your exhaust to the VIN of your M340i or M440i; fitting then falls to your garage, which works with clamps and gaskets, without welding or cutting.
Configure your exhaust.
How the exhaust is put together
On the M340i as on the M440i, our cat-back begins behind the B58's downpipe and ends at the two rear outlets: pipes, silencers and valves. The front section amounts to this downpipe and its catalytic converter; each product page lets you replace it through the "Manifold" option.
Each choice explained in detail, from sound to material: How to configure your exhaust.
Your exhaust for the M340i or M440i
First choose the product page for your body style, M340i for the saloon and the Touring, M440i for the coupé and the convertible. Then set the material, 304 stainless steel or titanium in three shades, then the timbre, straight pipe or resonator at the same price, add the downpipe if you want it, and decide who controls the valves: your driving modes or the Rog remote.
The price of each configuration is shown on the product page, in your currency.
Three recommended configurations.
-
Family Touring
- M340i
- Stainless steel
- No manifold
- Resonator
- Factory valves
For an M340i Touring that sets off loaded: the B58 takes on a rounder voice, the standard front section stays in place, and Comfort or Sport still decide when the valves open.
View this configuration -
Everyday saloon
- M340i
- Stainless steel
- 200-cell sports catalytic converter
- Straight pipe
- Rog remote
For an M340i saloon that is driven every day: a six-cylinder more present when accelerating, emissions control kept, and a remote to open it or silence it at will.
View this configuration -
Weekend coupé
- M440i
- Purple titanium
- 200-cell sports catalytic converter
- Straight pipe
For an M440i coupé or convertible reserved for fine roads: the exhaust lightened by titanium, a shade that signs the rear, and the B58's metallic song up to the red zone.
View this configuration
From order to fitting.
VIN, manufacture, delivery, fitting and warranty, step by step
Questions.
M340i or M440i: which product page to choose?
The M340i product page covers the G20 saloon and the G21 Touring; the M440i page, the G22 coupé and the G23 convertible. In case of doubt, the VIN entered when ordering lets us correct things before manufacture.
Is my 392 hp M340i, produced in late 2025, covered?
Yes. The M340i and M440i product pages cover the B58 in both its tunes, 374 hp and then 392 hp on cars produced since November 2025. The VIN of your car is, in any case, checked before any manufacture.
Is an M340i Touring G21 entitled to the same exhaust as the G20 saloon?
Yes: the M340i product page makes no difference between the saloon and the estate. Material, sound, front section and valves are chosen there in the same way.
Will the Sport and Sport Plus modes of my M340i still control the valve?
Yes, by choosing the Factory option: your BMW valves are transferred onto the Rog exhaust by your garage, and Sport or Sport Plus carry on opening them. By choosing the Rog option, the remote takes over, and the mode engaged makes no difference.
And for an M440i Gran Coupé G26?
The exhaust for the M440i coupé and convertible also suits the Gran Coupé G26, but this one is presented on its own product page, with its own guide. Your VIN confirms the product page to choose before manufacture.
Straight pipe or resonator on the M340i's six-cylinder?
To hear the B58 unfiltered, crackles included, take the straight pipe. For a family Touring or a cruising convertible, the resonator, priced the same, rounds off its voice and softens it slightly.
A question about your M340i or M440i?
Put it to the Rog Advisor or write to us: we reply in writing, within 24 hours.
Further reading.
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