Well I shot my buddy a message who has an SRT8 Challenger and is certified SRT8 tech, what I am doing is what he has on his Challenger, DI/DO 2 Chamber muffler with 3" pipes and where stock resonators are he has Super 10 series and has a nice sound. The difference is I went 2.5" pipes but everything else will be similar. He said with just the single muffler or what I have now it will be raspy which I hate.. We'll see what the end product is Saturday, worst case I cut off rear mufflers with down spouts..