ORIGINAL: pe reivers
I fail to see how preventing heat radiation can make a muffler system flow more gas. The gasses stay hotter, so have more volume that must exit that same little old stinger tube. Sound waves however travel faster, so a tuned system seems to become shorter by the hotter gasses inside, changing the engine tune.
I do not know,but I have seen many 2 stroke exhausts painted flat black. I guess the heat is radiated out faster. This may cause less volume inside of theexhaust systemneeded to pass out of it. Just a guess ! Capt,n