I have some sort of weird high flow catback that came off my car today, I’ll give pics and exact measurements soon, but for now all I can say is it is definitely of higher diameter than the stockie (I’m 90% sure it’s 2.5"), and is far more straight. The reason I took it off… my muffler came off and the car was making all sorts of loud noise. Now my car is slow anyway, so I wanted it to be slow and quiet atleast. This catback has a cat welded to it atm that you can either keep or cut and weld flanges to it. This is not a super nice exhaust, but it is a definite improvement over stock. I would reccomend it for N/A use, or if you have a stock boost SR.
Pics to follow, located in Woodbridge, best offer takes it. If you want I can throw in the muffler too for free so all you would need is a weld-job. (definitely use a different muffler if you’re turbo though)