Been looking for a three inch to 2.5" x pipe or h pipe to adapt 3" test pipes to a 2.5" cat back muffler system. Resonated or not. Many h-pipes I've seen are only 2.25" inside diameter.
Follow Ups
Does anyone make a 3" --> 2.5" x pipe or h hipe ? - TTkeeper13:45:04 06/30/18