Best Exhaust Setup for BMW G90/G99 M5: Sound, CEL, Downpipe, Valvetronic Exhaust, and Remote Control Guide

In this article series, Fi EXHAUST shares recommended setup based on years of experience in the exhaust and performance modification industry. Each guide is created to help owners understand how each setup affects sound, drivability, CEL risk, and most importantly, how to choose the right setup for their build.

For the BMW G90 / G99 M5, the factory exhaust system can be divided into three main sections: primary downpipes, secondary downpipes, and the catback exhaust system. Understanding these sections is important when choosing the right setup for your modification plans.

Many BMW G90 / G99 M5 owners ask:

• Will changing downpipes trigger a check engine light? 

• Is a catback exhaust enough to make the car sound better? 

• What is the loudest setup without touching the primary downpipes? 

• What is the loudest setup without touching the primary downpipes? 

For most owners, the right setup depends on one question: 
Do you want the best sound-to-CEL concern balance, or the most aggressive setup possible?

Our Recommendation Path for US-Spec G90 / G99 M5 Owners - Upgrade by Stages

If You Want the Safest First Step: Choose Fi EXHAUST Catback Exhaust System

Even with the primary and secondary downpipes kept in stock, the Fi EXHAUST Catback System can already deliver a noticeable sound upgrade, giving the G90 / G99 M5 a deeper, fuller, and more exciting V8 tone. This is the best starting point for owners who want to hear the car more, but do not want to make a big jump right away.

If You Want More Sound Without Touching the Primary Downpipes: Choose Secondary Catless Pipes + Catback Exhaust

The next step is adding Secondary Catless Pipes, compared with the first stage, this setup makes the exhaust tone louder, and more aggressive. Pops and bangs become more noticeable, and the car feels more alive when the valves are opened. At the same time, keeping the primary downpipe in stock, for most owners, this is the sweet spot. 

For most G90 / G99 M5 warranty-conscious customers, this is the setup we would recommend first if the goal is to make the car sound significantly better without taking unnecessary CEL risk.

If You Want the Maximum Sound and Performance

Primary downpipes create the biggest difference in sound and performance potential, but they also come with the CEL risk.

Once the primary downpipes are changed, the Check Engine Light will be triggered.

For customers who are planning ECU tuning or building the car for maximum performance, primary downpipes can be considered. But for owners who are still under warranty or mainly want a cleaner sound upgrade, we usually recommend keeping the primary downpipes stock.

OPF Model Notes

Unlike US-spec non-OPF models, for OPF models, the modification on any sections of the exhaust may carry CEL risk once the factory exhaust configuration is changed. Because of this, ECU software calibration is generally recommended for OPF models before or after upgrading the exhaust system.

We also recommend confirming the vehicle’s market specification before choosing the final exhaust setup.

Where to purchase?

#Available for both OPF and NON-OPF models

View More: BMW G90/99 M5 EXHAUST