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, Larini Clubsport exhaust, GMG springs, Satin Black badges
2012 Audi A6 Prestige, Moonlight Blue
2009 Lexus ES350, Sparkling Graphite
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