Hey guys, i have a pretty much stock Si, 93 lude, with a magnaflow muffler, and no resonator on stock pipes.

I was wondering what size piping would be ideal from the cat back to the muffler? Would it be worth it, any gains?

Do i have to have any resonators in there?


Thanks

William

 

i got 2 1/4 piping with i/h/e with resonator and i kind of feel some gain on the high end or maybe thats just me

 

Stock piping size is noooo good

 

2.5" here

 

ok so which is best 2.5 or 2.25?