Royal Muffler, based in California, is for most of us probably an unknown in the tuning world. They have experience on their side though with more than 30 years of experience upgrading exhaust systems and the performance of sports cars. Their latest project is this black-white BMW E92 M3. Unfortunately, we cannot give you any details on the output and price, but we can show you this promo video and gallery of the vehicle. Scroll down and enjoy!