The M3/M4 exhaust has been loved by some and hated by others. With the introduction of turbo technology into the latest generation of M3/M4 vehicles, they simply don’t sound the same as the older V8 engines.
Before we talk about the actual exhaust, let’s discuss why turbochargers were added to this generation of vehicle. The turbo chargers were added for a few main reasons, namely additional horsepower/torque through relative easy means and fuel economy. Turbos were used decades before as an easy way to get ridiculous amounts of horsepower and were releveled as a miracle. Nowadays, turbos can be found on numerous cars from the 328i to Porsche 911s. The turbos did add some additional horsepower to the F80 M3 but the biggest difference being the torque. With over 100lb-ft of torque above the previous generation and at only 1850rpm, this car seriously launches. Once the torque kicks in, you really feel it. The car really starts to go. More torque generally equates better off the line launches. The M3 however does have trouble putting down the power even in 3rd gear on dry roads. Turbos are used in a variety of luxury vehicles to reduce fuel consumption while maintaining a respectable amount of horsepower/torque. With the EU increasing their restriction on fuel consumption and the US making similar measures, BMW decided that it was the only feasible way to go. More and more restrictions are inevitably going to come and there simply has to be a point where newer technology has to come into play. Like any new innovation, there are benefits and negatives.
The M3 exhaust can be adjusted via the throttle button located on the center console. In efficient, the valves tend to stay closed most of the time unless in WOT. In sport and sport +, they really do open up but at highway speeds and low rpms, they close back up. The reason being is that there tends to be a drone otherwise.
In terms of how the exhaust sounds, I don’t think it’s that loud but it’s not that quiet either. At cold start it can be quite loud but in efficient mode it’s quite tame. On a cold start with the valves open, the entire house shakes. In an enclosed garage, it actually does hurt my ears. Driving around in efficient, I think that there is almost no sound. It could be easily mistaken for any other 3 series sedan. Once you put it into sport and sport +, there is a lot more noise. The valves open up at higher rpms, in you really have to drive more aggressively or keep higher rpms in order to hear the exhaust sound. I personally would prefer driving around in efficient but with the exhaust note as loud as it is in sport mode. I personally think the exhaust is acceptable. It’s not as good as some of the other exotics but it’s not a wimp either.
There have been a few instances where I’ve gotten comments from strangers. Mostly compliments and how good the exhaust sounds. I’m honestly surprised as many M car owners have had negative things to say about the exhaust. I think to most people who are not into cars, it sounds great but to the seasoned car enthusiasts it might be lacking. The downshifts are really nice and have turned more than a couple of heads. It can’t be that quiet now can it?
Overall, I think you buy the vehicle for the driving experience. Sure the exhaust note is part of it but you don’t buy a car just for that do you? I surely wouldn’t. I can’t call the exhaust great by any means but I don’t think it’s as terrible as others have said it is. With the valves open it stands out from your typical 3 series. If you’re on the fence about the exhaust, go listen to it in person and you might change your mind for the better or the worse.