I made mufflers out of the newer metal lightsabers that come with Attack of the Clones yoda figures. I found some yodas at walmart for 4.99 each. Not only does my son get new figures but I get new mufflers at a decent cost imo compared to other metal mufflers and they are pretty good right out of the box. No mod except I removed car body muffler and some crazy glue. And the darth vadar lightsabars would make sweet ass straight pipes for wild-g trucks. Ill try that soon