We can easily start a database of the SPL of the different exhaust available for the 250. There is a free app for the iphone from JL Audio that has an SPL meter. App Store - JL Audio Tools. I know alot of people have iphones. We can set a standard like setting the phone on the seat and measuring at idle and at a higher RPM also. People can post their exhaust type and the SPL. What do you think??