There used to be a Walker Exhaust general catalog online, in addition to the DynoMax catalot, which is similar. Pipes, configurations illustrations, clamp sizes, AND the spec section in the rear will generally answer any questions you might have on case sizes, pipe sizes/offsets, etc.
My '67 Newport came with the 383-4bb, AND the factory single exhaust. An unusual situation as the similar Plymouth and Dodges had dual exhaust from the factory. All rated at 325 horsepower! Using the stock y-pipe, I adapted the Imperial 2.5" muffler and middle pipe to the y-pipe's ball joint end. These were 1974(?) Imperial parts. I used the rear pipe w/o the resonator, but had to get it bent upward to exit closer to the rear bumper, as stock, but that was the ONLY real thing I had to get done, that I couldn't do myself. Everything fit "as designed", with stock hangers.
That Imperial muffler is the normal C-body size of case, but with the 2.5" pipe inlet and outlet sizes AND the same low restriction of the Street HEMI muffler. Still stock quiet. I believe the stock pipe sizes are 2.25" inlet and 2.0" outlet, or 2.25" for both?
I like factory-configured exhaust system parts I can do in my driveway rather than the welded systems which muffler shops like. Over the years, the quality of muffler shops has been known to be very variable, by observation. Which is one reason I like the Walker brand (which NAPA sells under the Walker part numbers) as they fit perfectly. Factory-style clamps and hangers are listed, too, which is another plus, to me.
CBODY67
