BMW M5 G99: Akrapović exhaust and Eventuri Carbon intake

The model presented in our workshop is an M5 Touring G99 in Full Black configuration with black rims and red callipers. Interestingly, the owner had the '50 years BMW M' logos added, which were not originally present on this model when it was delivered.

This new-generation M5 is distinguished by its plug-in hybrid system. On start-up, the car is almost completely silent, running in electric mode. While this technology delivers impressive performance on paper, it unfortunately erases the sound character that is the DNA of BMW M sports cars.

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In our first sound test in the video, the conclusion is clear: the original sound of the M5 G99 is very artificial. There's clearly a 'speaker noise' coming from the Active Sound Design rather than a real mechanical sound. For a twin-turbo V8 producing over 700bhp, this is a shame, not to say disappointing.

Underneath the car is a complex exhaust system, with catalytic converters, particulate filters, an intermediate silencer and a rear silencer with electronic valves. Everything is designed to muffle sound and comply with environmental standards, to the detriment of listening pleasure.

To add character to this M5, we installed an Akrapović BMW M5 Slip-On Line (cat-back) exhaust system in titanium. This system represents the perfect compromise between performance, sporty sound and legal compliance.

Technical characteristics of the Akra exhaust system

The Akrapovic BMW exhaust chosen is a Slip-On, which means that it replaces only the rear part of the exhaust line (rear silencer and connecting pipes). This configuration offers several major advantages:

• Keeping the DPFs: The original particulate filters remain in place, which means that the manufacturer's warranty is maintained and the car complies with anti-pollution standards
• Titanium material: High-quality titanium construction, lighter and stronger than the original stainless steel
• Weight savings: -6.12 kg compared to the original exhaust system
• Specific tailpipes: diamond-shaped/octagonal shape in carbon and titanium, specially designed to fit into the G99 diffuser

Exhaust design and integration

An important point raised during installation was the new diamond-shaped tailpipes. At first, the team was sceptical about this design, but once installed, the verdict was unanimous: they blend in perfectly with the angular design of the rear bumper and fill the space in the diffuser much better than the classic round tailpipes.

note that Akrapović also offers a version with round tailpipes for those who prefer a more traditional design, as well as a carbon diffuser (not yet available at the time of the video) to complete the rear aesthetic.

Valve Management and Technical Limitations

The akrapovic bmw M5 exhaust retains the original electronic exhaust valves. One important point: Akrapović does not allow the installation of a manual valve management module (Sound Kit) on the Slip-On version. Why not? To avoid engine trips due to variations in back pressure in the DPFs, which could lead to ECU errors.

The price for this BMW M5 G99 Akrapović exhaust system is approximately €7,390 including VAT.

The second key element of this transformation is the Eventuri matte carbon intake kit. This intake is much more than just an air filter: it's a complete system that rethinks the engine's air supply.

Eventuri design and technology

The BMW M5 Eventuri carbon intake consists of several components:

• Matte carbon airboxes: Full replacement for the original airboxes, with a matte carbon finish to match the original engine cover of the M5 G99
• direct intake scoops: Located just behind the grille to force fresh air in
• Sealed system: Closed design to prevent hot air being drawn from the engine compartment
• Optimised airflow: Designed to improve flow and reduce turbulence

Performance of the Eventuri intake

According to the Eventuri manufacturer's data, this intake kit provides theoretical performance gains of +14bhp and +14Nm of torque. Unfortunately, at the time of our visit, it was impossible to verify these figures on the test bench: the car was brand new (138 km) and still in its running-in period, electronically limited to 4,000 rpm.

Power figures aside, it's in terms of sound that the eventuri BMW M5 G99 makes all the difference. Once installed, the intake makes the noise of the turbos audible: you can distinctly hear the spool (pressure build-up) and the discharges (pschiit) of the two turbos, creating a mechanical ambience that is totally absent from the original.

This feature transforms the driving experience, even with the windows closed. The intake becomes a veritable mechanical concert, a constant reminder that under the bonnet is a twin-turbo V8 and not an electric motor.

The price of the BMW M5 eventuri carbon intake kit is around €2,890 including VAT.

Installing these two performance parts requires several hours of painstaking work:

• Preparation: placing on a bridge and removing the thermal protection under the chassis
• Removal of the original: Dismantling the rear exhaust system at the connection points after the DPFs
• Installation of the intake: Removal of the original airboxes and installation of the Eventuri carbon boxes with their scoops behind the grille
• Fitting the Akrapović: Installation of the titanium rear silencer, adjustment of the link pipes and reconnection of the electronic valve motors
• Final adjustment: Precise alignment of the tailpipes in the diffuser for a perfect aesthetic finish

Before/After comparison

Before (Original sound) :

• Artificial "speaker noise" sound
• Muffled and muffled on the outside
• Total lack of mechanical character
• No sense of the turbos

After (Akrapović + Eventuri):

• Exterior: Deep, sporty sound, presence of clearly audible burbles when the throttle is released, less metallic than on the S58 engines
• Interior: The Eventuri makes the turbos perfectly audible
• Character preserved: The sound remains civilised because the FAPs have been retained

Road test: Sensations rediscovered

During the test drive, the change is immediately perceptible. under acceleration, the suction of the Eventuri intake is very pronounced, with the song of the turbos in the background. The burbles when the foot is released add a sporty touch that was sorely lacking from the original.

Total investment and performance/price ratio

For a total budget of around €10,000 including installation, this transformation corrects the BMW M5 G99's main shortcoming: its lack of voice and engine character.

This BMW M5 G99 equipped with Akrapović exhaust and Eventuri carbon intake finally becomes the sports car it should have been from the start. For enthusiasts who find the M5 hybrid too sanitised and quiet, this modification is a must.