I am planning on doing the full high flow cats and midpipe upgrade to go along with my Eisenmann muffler. Dunno when I am going to do it though given all my expenses this year along with getting married in August. Why not just take it to a good muffler shop? The secondary cats have nothing to do with O2 sensor.
2012 Audi R8 V10, 6MT, Suzuka Gray, Capristo X-Pipe, Klassen M52R, GMG springs, R8 GT tails, Satin Black badges
2012 Audi A6 3.0T Prestige, Moonlight Blue
2015 BMW X5 35d, Mineral White
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