1959 black 270hp (9/2/69) 1981 Beige L81(10/20/80)
Are they GM style sidepipes or header sidepipes? If original Corvette pipes (1969) there isn't much you can do. There is not really any room to add any kind of additional muffler. If Hooker style header sidepipes there are options on the muffler inserts. I was looking at the systems online a while back at some of the Corvette parts houses and they list a loud or a quiet insert.