i was wondering does anyone know of where or if anyone makes a performance muffler for the stock diameter piping on a ram 50? and also i was wondering what size the piping is i think its 1.75 but I'm not sure

2" is the size for the stock exhaust - take your pick of brands - flowmaster, dynamax, magnaflow, and on and on. For the best results, have a muffler shop make new pipes from the cats back; there are usually 2 cats - 1 in the exhaust manifold, and one just below. If you are running the stock carb, don't increase the size of the pipe or you will lean out the engine and burn out things; rejetting the stock carb is not really an option as there is little if any parts for it around.

are you sure its 2"?

I think my trucks stock exhaust was 2 inches. I had a cat below the cab and the exhaust itself was under the bed. Don't have the g63b in it anymore, or the oem truck piping anymore. Sorry.