Ok so here's the big cat i'm talking about... 3rd cat in the system (2 pre-cats before this one on the y-pipe):
Here's where the o2 bung was put in to keep CEL's from coming on (re-used the factory hangar):
And here's what it looks like with rear cat delete in place. 2.5in tubing 1 piece from the big cat back to the muff:
I highly recommend this for anyone, especially with higher mileage motors. Helps to open it up quite a bit. More so than I thought it was going to. My truck used to be quite quiet. Had 2 different types of muffs on it and neither one was "loud". The cats are HIGHLY restrictive, and with this mod in place, it proves it.
EDIT: Here's the cat I'm talking about that I took out. Thanks for the pic Malydeen:
You can see where it's about 2.5in off the cat and where it reduces down to about 2in at that collector. When you do this mod you take out the cat and run it 2.5in all the way back increasing flow by a good 25% just in tubing diameters.
FXEdgeplorer Level II
Part 01, 02, 03, and 06
Tall, Slow, Shiny, Loud
6 Lug Ranger
D44 SAS'd on 12" of lift and 37's...