noobish exhaust question about 2.5" exhaust

[PRO®]

I was wondering if I got a 2.5" exhaust and put a 22" resonator on, would I see any large drops in performance? Right now, I am running a gsr with the d-series piping(don't know the diameter), and i feel as though it is restricted. Problem is, I want it to sound as stock as possible. Would a 14" resonator sound stock? Two Resonators? Also worth mentioning, I was thinking of using a Rsx-s or 06+ Civic si muffler. Any insight? thanks

[KevinT707]

In general resonators such as Magnaflow are straight through; it has sound deadening material + it's resonated on the inside. Those will not affect anything performance wise; I run a 22" Magnaflow on mine & it quieted it down enough for me. On the other hand I've never looked at an OEM resonator so I wouldn't know but I don't think it will affect performance.