... because I just put new MB mufflers on.

But now the quiet rear makes the noisy engine much more apparent ... a lot of taps, clicks, and the like. This is a 450SEL with engine bay foam noise insulation, so it shouldn't make this racket.

Any ideas on what the problem / solution may be? I'm wondering if it's something as simple as needing a valve adjustment, or something more complicated, such as a worn cam.

Thanks