Greddy Supreme SP Exhaust 2012-2015 Honda Civic Si 2 DoorThe Supreme SP for the 9th generation, (FB) Civic Si features our signature GReddy layout, styling and sound, with new revised piping diameter. It is designed to be compatible with both Si models; coupe and sedan (using the optional 11050108 adapter.) The straight through resonator and specially made oval muffler with off set extended tip allows the system to follow the Civics bodies lines and help reduce drone and high pitch frequencies. It also