I may have invented another crazy muffler mod.
Whilst doing a Crios mod last year, my drill bit fell inside the muffler!
It has been rattling around ever since so I have a spare s muffler which I will fit sometime.
Soo I thought I would recover the drill bit so I drilled/cut a hole on the underside of muffler - halfway from front to back and inline with outlet tip in a flat area. Using a magnet and borescope I recovered the drill. I was going to cut an alloy patch for the hole and screw or rivet it on..... BUT I had to start the car to see what it would sound like
Well...... it sounds pretty darn good! Instead of sounding like an exhaust leak it has a deep growl like a sport exhaust! No drone and a nice burble on the over run!
I guess it is just a more extreme Crios mod as the opening is still in the central chamber - just a more direct exit.
I also feel that I have got back the low down torque I lost when I put on the secondary cat delete pipes.
Obviously this would not pass a smog visual check but I wonder if the opening was on top of the muffler it could have a pipe routing to the exhaust tips. A sort of bypass.
I will take some photos and video in the next few days.