---tab Description--- SPELAB's downpipes are designed to seamlessly fit in place of your restrictive stock downpipes, which are situated immediately after your catalytic converters. Upgraded downpipes provide great increases in horsepower and torque on turbocharged vehicles by allowing exhaust gasses to flow easier as they leave the turbo. The high-quality exhaust manifold can improve the exhaust air flow rate and ensure you have a better driving experience. Key Features Improve Engine Output and Efficiency, Give you extra HPs, and increases torque Large diameter and free flow tubing for unrestricted flow, Making the exhaust air flow smooth, Designed for high-performance racing Made of High-Quality 16-gauge T-304 Stainless Steel with Computerized Mandrel-Bends All joints are TIG welded to prevent cracking and wear CNC Machine Flange for MAX Strength and Durability Flanges chrome plated for corrosion resistance Specifications Certificate: ISO9001:2000 Application: Exhaust Down Pipe Material: Stainless Steel Surface: Mirror Polish Model: DP29749 Pipe Inlet Diameter: 3" OD Pipe Outlet Diameter: 2.5" OD Pipe Thickness:16 gauge (1.5mm) What Does A Downpipe Do? The downpipe exhaust on your turbocharged vehicle is directing the exhaust gases out of the turbine housing into the exhaust system. An aftermarket downpipe will typically be larger in diameter and either use a high-flowing catalytic converter or remove the catalytic converter altogether. By removing the factory downpipe and replacing it with a high-flowing unit you are allowing the turbo to move gases away from the turbine which creates more power. Since the factory restrictions are now gone you can increase the boost on the vehicle as the factory downpipe is a choking point for performance. ---tab Fitment--- 2011-2013 BMW 550i 2010-2013 BMW 550i GT, xDrive 2012 BMW 650i, xDrive 2009-2012 BMW 750i, xDrive 2009-2012 BMW 750Li, xDrive 2011-2012 BMW Alpina B7, xDrive, B7L, B7L xDrive 2010-2013 BMW X5 2008-2014 BMW X6 Will NOT Fit the M Series Models ---tab Shipping & Returns--- Fast Shipping Policy Your order will be dispatched within 1-2 business days, and the package will arrive within your order's estimated date. Click for Shipping Policy Easy Return Policy Every order comes with a 14-day free return, which means you don't have to pay for a return slip. Click for Return Policy