GSR Header and Exhaust Install We just received our new Yonaka 4 to 1 header, and Yonaka Cat Back Exhaust. Our shop car is a 1992 Civic DX with a GSR swap. Here are some pictures before and after. Yonaka Civic Cat Back Exhaust – $260 Yonaka GSR Header – $225 Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related