So I am thinking about building a catback system for my xj8 and have a few concerns.
When I first got the xj8 I removed the first 2 resonators and replaced with straight pipe leaving the stock mufflers in place, this developed a knocking sound at the location of the first resonator and a rattling sound out of the mufflers. I replaced both resonators and everything sounds fine, but after searching youtube I heard some great sounding jags with magnaflow exhaust. Here is my idea for the system:

1. remove all stock exhaust from cats back.
2. run 2.25 pipe from cats to x pipe.
3. place x pipe where resonator 1 was located.
4. 2.25 pipe out of x pipe down the center like original.
5. Magnaflow mufflers with 4in tips.

I am concerned that the knocking sound might return with resonators removed if any on has any experienced this or has a better idea I would love to hear it, I looked at quicksilver exhaust and theirs looks similar to my idea and I did not see any resonators in their system so I am assuming that this knock had something to do with the stock mufflers not allowing the flow of exhaust.

 

shouldnt hear a knocking sound unless it was broken up catalytic material. I wouldn't worry about it. Id also go 2.5"