8TH Gen CT Engineering Cat-Back Exhaust: Compatible With 06-11 Honda Civic Si Coupe, Can Also Fit Sedan With Some Modifications! The Rev9 full cat-back exhaust system for the 06-11 Honda Civic si 8th Generation. If you own a 2006 to 2011 Honda Civic SI, whether it’s the 2-door coupe or https://www.thehondaautoparts.com/product/8th-gen-ct-engineering-cat-back-exhaust/