Metallic catalytic converter HJS, 100CPSI kit for OEM headers
(Weld on connection)

This Supersprint downpipe kit  replaces the awfully restrictive, BMW factory, US M3 cats with HJS Motorsport, high flowing units.

The flow rate is virtually the same as the Supersprint cat-deleting straight pipes, yelding to substantial performance gains across the entire rpm range.

Installing this kit requires welding the new downpipe assembly into place, going unnoticed from a visual check.

The Supersprint cat system has O2 bungs and EGT threaded provisions, and factory-spec flanges, for a perfect fitment in conjunction with the Supersprint front exhaust section and with the stock exhaust, as well.

The Supersprint cat system has O2 bungs and EGT threaded provisions, and factory-spec flanges, for a perfect fitment in conjunction with the Supersprint front exhaust section and with the stock exhaust, as well.