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We're both excited and proud to announce the release of our B5 A4 Turbo-Back Exhaust System, OEM-style Replacement Catalyst, and Replacement Test Pipe!





Bolt-On Power and Torque


When designing the 1.8T Audi thankfully increased the size of the K03 turbocharger. Unfortunately they designed the downpipe like a brick wall. Rule #1 in turbocharger theory is reduce backpressure at the turbo discharge. With the factory downpipe installed, exhaust gases exit the turbo and wastegate only to meet a dense catalytic converter. By increasing the size of the piping to 3" and moving the catalytic converter further away from the turbo, exhaust gases can mix naturally and develop momentum before being filtered through the catalytic converter. The result is useable power and torque throughout the powerband, quicker throttle and boost response.






Attention to Detail


Starting at the turbo, a CNC machined flange allows gases to merge naturally through a Magnaflow 200 cell metal catalytic converter (or, for race use, a test pipe). The second bend transitions the downpipe neatly through the exhaust tunnel, separated by a stainless steel flex section. Underneath the car, a custom threaded spring bolt assembly allows the downpipe to be supported by the factory hanger. Bolting to the downpipe flange, a virtually straight midsection packs a free-flowing resonator to help eliminate drone. Meeting our midpipe is a tail section with a deep, distinctive Magnaflow muffler, which then leads back to a dual outlet tip section. Double layer graphite gaskets and grade 5 locking hardware keeps everything tight.





Construction:


Construction Highlights:


-CNC mandrel bent aluminized steel tubing

-CNC waterjet cut 1018 cold roll steel flanges

-Professional TIG welded construction throughout

-409 stainless steel 200/cell metal catalytic converter

-Stainless steel double-braided flex section

-High-temperature vermiculite gaskets

-Grade 5 locking hardware

-CNC machined hanger assembly cad/zinc plated steel





Construction Highlights (Stainless Steel Upgrade):


-CNC mandrel bent 304 stainless steel tubing

-CNC waterjet cut 304 stainless steel flanges

-Optional CNC machined male/female v-band flanges

-Professional TIG welded construction throughout

-409 stainless steel 200/cell metal catalytic converter

-Stainless steel double-braided flex section

-High-temperature vermiculite gaskets

-Stainless steel hardware & copper coated locking nuts

-CNC machined hanger assembly stainless steel



Includes:


-Complete Downpipe Assembly

-Catalytic Converter OR Test Pipe

-Stock Exhaust Adaptor

-Downpipe Gaskets & Locking Hardware

-Installation Instructions


Also Available!

For those looking to purely meet a maintenance need, we also have OEM Replacement High Flow Catalytic converter options available, in addition to OEM Replacement Test Pipes for track use.


B5 A4 OEM Replacement Catalyst Section



B5 A4 OEM Replacement Test Pipe





Pricing:


Street Series Turbo-Back starting at $930

Race Series Turbo-Back starting at $855

OEM Replacement Test Pipe starting at $220

OEM Replacement Catalyst starting at $295



ORDER NOW!



For more information, further construction details, and FAQs please visit our product page located here.


--------These components are only guaranteed to fit on Quattro models!---------