I've already done a muffler delete and I like the sound, but it has me itching for more. I'm planning on installing a Vibrant Resonator. One concern I have is that on the IS 250, the resonator goes in as two pipes and out as two pipes. Do I need to purchase two resonators? Or do I need to just get the mechanic to weld a y-pipe? If you've done a resonator delete or swap, how did you set up your pipes? I will attach an image of the resonator. Any help is appreciated.

 

If the setup is the same as the IS350, I remember it has a resonator on each pipe, so I believe you will need 2 of these

 

The midpipe itself has one resonator and 2 catalytic converters. They go from the 2 cats on the headers to the 2 cats on the midpipe after the secondary O2 sensors then are Y piped into the single resonator(stainless part below).

 

Hope that helps gives you a good idea.