blew out a muffler today

I knew a feller who had one of them there Knock off Jine-ease carburetors. Apparently it was dumping fuel and loaded up the cylinders so bad that when he finally got it to fire it blew his passenger side muffler to Kingdom come...I looked under the car and the muffler was wide open like the gash in the Titanic...I looked at him and said "what the hell happened here? did ya have a muffler explosion?"