
I recently bought a 2003 BMW 540i. It has a 4.4 liter V8 engine and the previous owner had the brilliant idea of removing the stock muffler and sound box. The car was loud as hell when I bought it and I had to babysit it to avoid waking up the whole neighborhood and getting the attention of every cop within a three mile radius. Now, with just that muffler and no resonator, this car is as quiet as any other on the road under normal driving conditions. As the revs increase, the engine still gets noisy, and it's good noisy. In the cabin, the exhaust is barely audible due to road noise. That's pretty much what I was aiming for, which is to turn this car into a suitable everyday driver.