My car has a custom 4inch down pipe that was made by the previous owner, there used to be some documentation about it on this site but since the upgrade I've been unable to locate it. However, I'm changing my downpipe to run out the bumper. I was curious if anyone with a hellion kit would be interested in replacing their 3 inch down pipe with this 4 inch setup. It splits into a 3 inch y which I also have the catback with magnapacks I can throw in with it. I have no idea what to ask and have no idea if there is any interest.