APR B6 S4 Downpipe
Description
A set of downpipes is also available for the 6spd S4's. This system replaces the 4-cat factory setup with a pair of metal matrix catalysts. APR downpipes will only fit with an APR catback system. In testing, a full APR exhaust produces gains of 25hp and 35lb-ft across most of the engine powerband. Throttle response is also greatly improved.
