Anyone know I.D and O.D of the oem exhaust system & muffler.

 

Bear in mind it will vary a bit due to bends and flat sections. I measured: Inlet to flex at Turbo out = 2.91" ID (Flex is approx 4" at outside of metal mesh), CAT1 in=3.0" OD, CAT1out/Cat2in = 3.03" OD, CAT2out=3.01" OD/2.85" ID, Resonator(out) = 2.5"OD/2.3"ID, Muffler(in)=2.53"OD, Muffler(out)=2.75"OD. Maybe someone else can "fill in the blanks" but that covers most of it.

 

Do the muffler delete!!!