So you are saying that you got 13 whp from just the muffler? Seems high...
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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