MAZDASPEED3 Gen2 SS 3" Cat-Back ExhaustMFG# 572101 DESCRIPTION The layout of this COBB 3" SS Cat back was chosen to minimize the total bend degrees used to route the exhaust piping for reduced back pressure. The entire system fits within the factory exhaust path to allow the exhaust to be tucked up as close to the undercarriage as possible to achieve maximum ground clearance. Exhaust piping is 3" diameter from the downpipe to the split, where dual 2. 5" pipes whisk the exhaust out of the