Not sure which 2005 Ford Focus Performance Mufflers are right for you? We have over 627 customer reviews, with an average rating of 4.5, to help you find exactly what you're looking for. Timothy V from Glen Rock, PA said, "This actually increased my top end by a noticable amount. I had an AEM cold air intake installed about a week before I put this on. Not too loud and not to ricey! A very good buy"