you should try the flo pro force mufflers from summit. for laughs i put my stock headers upside down and put the mufflers to the headers. quiet enough at idle with f cam and mellow but mean at the same time when revved. i put them up to the long tubes though and much louder but still not too bad. but with the thumper heads, they are quite a bit louder now. this is without the o/r bassani x pipe. the mufflers are only 30 bucks each and are built just like flowmaster. you should look into them. they are great.