Back in the day I bought a 2.5" exhaust from JGY and I am pretty sure it came with that exact resonator, the big magnaflow. I still have it on the car today except I changed out the Magnaflow canister style muffler for a Flowmaster 60 series muffler. The 60 series is the quietest one the make. I really like exhaust with the flowmaster a lot...it is so much quieter than when I had the canister style muffler on it. It kind of has this "hollow/mellow" type sound to it, I gotta post up a sound clip. I believe the resonator has a lot to do with the nice sound I get. By the way this is on a turbo B13.