Increase in boost?
Late to the discussion but just wanted to comment:
Great post and follow up! I'm really starting to contemplate an exhaust mod myself.
One question if nobody's asked. You mentioned you were able to measure an increase in turbo boost to 12psi? And that was just with the middle resonator replaced with an x pipe? Apparently that middle resonator is very restrictive.
12psi is huge (for a non race car)...You must have noticed an appreciable step in acceleration. Was it off idle, midrange, or top end?