Scope of delivery:- Downpipe for Audi A4 A6 1.8T B6 Quattro ø 63.5mm 2.5" made of stainless steel with interlock flex pipeProduct description: - The downpipe is located between the catalytic converter and the exhaust system. It is bolted to the original catalytic converter, or our plug & play 200-cell catalytic converter with item no. 340106 can be used. It has a diameter of 76mm (OEM 54mm), an interlock flex pipe is installed. The larger downpipe reduces backpressure, relieves the turbo, and allows for higher performance—depending on installed components, up to 450hp. The pipe is bent and welded only at the flex piece and flange. To connect to the original exhaust system, a reducer sleeve from 76mm to 55mm must be used, but most of the time, larger exhaust systems are used in tuning.Compatible with: - Audi A4 B6 1.8T Quattro 150hp, 163hp, 190hp AVJ, BFB, BEX - Audi A6 C5 1.8T Quattro 150hp AEB, APU, ANB, AWT, ARKand also for the following upgrade turbochargers: - Borgwarner K04-015 53049880015 - Borgwarner K04-015 / K06 - Borgwarner K04-015 / TFSI compressor wheel50% promotion for parts certification: We are looking for someone with an Audi A4 B6 1.8T BEX engine code in the Hamburg area who will make their car available to us for 4 appointments for a parts certification (ABE) (1-2 hours).1. Appointment noise measurement in original condition.2. Appointment performance measurement in original condition3. Appointment noise measurement after installation of the downpipe 63.5mm 2201544. Appointment performance measurement after installation of the downpipe 63.5mm 220154The installation of the downpipe can be carried out by yourself or, for an additional charge, at our partner workshops. If the measurements with the larger downpipe 76mm 220178 are within the tolerance range, you will receive a parts certificate according to § 19 (§) StVZO. This allows you to have the downpipe registered without any problems.Registration: For individual approval according to §21 StVZO, please ask your TÜV inspector. Please note that the installation of this item constitutes a modification that causes the vehicle's operating permit according to StVZO to lapse. Not permitted for use on public roads.