I did a search under "stock exhaust size" and "stock exhaust", no information about piping size I could see came up. I then read up to page 28 in the Mazda3 forum with no information either. What is the stock exhaust pipe size for an 07 Mazda3 s Sport Hatchback with a 2.3L? I crawled under the car today and measured the muffler, it's about 14.5"LX 7.75"W. I want to replace just it with a Dynomax Super Turbo muffler, more flow without any more noise. Muffler #17763 looks like the choice, is 2" offset in & out and very close to the same size as stock. The stock tailpipe is 2 1/8" if I measure right, the stock tip is 3". I'm pretty sure that muffler will work, just want to make sure.
Jim