FWIW - I talked to a muffler shop manager today and he stated that industry standard is that <span style="font-weight: bold"><span style="text-decoration: underline">exhaust pipe uses OD </span></span>to indicate its size for clamps and <span style="font-weight: bold"><span style="text-decoration: underline">mufflers use ID</span></span>. So a 2 1/4" exhaust clamp will fit over a muffler inlet/outlet with a 2 1/4" ID. In other words the 2 1/4" clamp will accomodate the larger (actually measured at 2 3/16"
outside diameter of the muffler inlet/outlet.
Anybody buy Ricks or Steves clamps pictured above?
Thanks