The BMW M4 CSL was revealed back in May, with production beginning in July, and already, someone has modified the car with a new exhaust system.

With just 1,000 units to be built and far fewer coming to the US, you'd think that buyers would want to keep it completely stock to preserve its resale value. Still, Valvetronic Designs, based in Quakertown, Pennsylvania, has plenty of customers who don't care about that. One such individual recently purchased an M4 CSL and, having owned various McLarens, Porsches, and more, felt that the limited-edition Bimmer was not loud enough, even though it comes with a titanium rear silencer as standard. Thus, he contacted the exhaust specialist and got a new mid-section installed.

You can see the installation in the short video below but be warned: watching someone cut the exhaust on a brand-new collector car like this may hurt.

Valvetronic Designs has fitted a single mid-pipe to the car, which fits between the factory downpipes and the factory titanium silencer. According to the company, the standard titanium silencer does help to give the M4 a slightly different sound compared to the regular M4 Competition, but the problem is volume.

With the new mid-pipe, the company estimates that the car is roughly 30-40% louder, which makes for a "very aggressive sound [that] is not overbearing." Based on what we can hear from the video, it seems that this is an accurate evaluation, and even in Sport Plus mode, the noise is not excessively obnoxious.

Still, we can't help but feel a little sad that a car as unique and rare as this has had its specially tuned exhaust slashed up in pursuit of more volume, but then again, this is not our car, and it's not our money being spent. As long as the vehicle makes its owner even happier, who are we to judge?

As a reminder, the M4 CSL features the same 3.0-liter twin-turbo S58 engine as the regular M4 Competition but produces 543 horsepower, up 40 hp over the standard M4. In addition, weight has been reduced by 240 pounds to 3,640 lbs.

With this relatively subtle modification to the exhaust, we're sure this CSL owner now has a couple more ponies and a little less weight to play with, and since he uses his $139,900 car on the track rather than locking it in a garage for all eternity, we must tip our hats and give kudos.

What are your thoughts - keep a limited edition like this factory fresh, or have as much fun as possible? Let us know in the comments.