Good plan! I really want to hear how that borla sounds welded in. The midsection is pretty easy to rebuild. As far as headers go, honestly the cheap ebays are actually really good. They are supersprint replicas usually and sound awesome and for our application, perfect. For the price, I don't feel bad about modifying either to suit. I still have to add cats at some point to mine and I'll put provisions in when I put the new system together.

You are correct about the mufflers. You have a straight through with louvers, or if closed, a highly acoustically arranged internal route. The valvetronic mufflers have a wireless controller that plugs in to them, and can automatically open to a desired certain percentage based on RPM or anything in-between. It gets a wireless OBD signal. There are a few apps as well out there that work universally. One from remus comes to mind. These valvetronic exhaust systems run can be found for various applications ranging from about 2500-7000.Should work out pretty sweet, and we will find out.

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2005 X5 3.0, 6MT, Alpine White on Truffle Brown, Sport, Preim, and Cold Weather, Alpina Stainless Headers, AFe Intake, UUC SSK, OEM 87's, 3.64 Differential Swap,Performance Modified Euro 2 Tune, UUC LTW Flywheel and HD clutch, Bilstein B12 Suspension kit
Future mods ZHP/Schrick Cam Shaft upgrade, Operation code name:Doppelschrauben-Kompressor

Wife's Ride: 2011 e70 X5 351 M///Sport.

Also in the fold: 2004 X3 3.0, 6MT, Black Sapphire on Terracotta, port, Premium, Cold Weather.