Here are my details from a few previous threads; Magnaflow x pipe with B&B Triflo.
Overall the fit is great in the same position as the factory resonator. The shop originally had the X within 1/4 inch of the rear diff coupling for an extra tight fit, looked great, but there is some movement in the diff which created contact. They re-did the cut angle on the pipes exiting the cat/crossmember area creating a little more clearance. No need to flatten the pipes, although my shop did make the whole unit smaller by taking off the magnaflow "inlets" to the X.
Overall the sound with the X is great, the Triflows do have bass between 1500 and 2000 rpm, sound strong on startup, but settle down at idle once warmed up. I have some clips with my camera mounted underneath the car at speed that I'll post.
I paid $290 for the custom X Pipe, all stainless 2.5", welded, magnaflow X and B&B Triflo install.
Simon
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