[sambo]

Tom, I remember reading an article on the web, very scientific in nature but it proved through a series of tests that it was possible to build a very quiet exhaust with no power loss. It involved 'tuning' the entire system from intake to exhaust tip, using resonator boxes in the right places to balance out pulse waves, etc. But while it is technically possible, the problem with the Cobra is that sidepipes do not allow for silencers, resonators, crossover pipes and so on due to their position and short length. I'm sure with some effort that it is possible to get close, but 90db is pretty damn quiet for a 'tricked out' 427!