Balloon Powered Single Cylinder Air Engine Open Chassis

Balloon Powered Single Cylinder Air Engine Open Chassis is an open chassis balloon powered vehicle that incorporates my Single Cylinder Air Engine ( https://www.thingiverse.com/thing:2870866). Video of Balloon Powered Single Cylinder Air Engine Open Chassis in action is here: https://www.youtube.com/watch?v=wkyOi47r9Io, and a cad animation of the model is here: https://www.youtube.com/watch?v=XMmz6TVZupg. We race these vehicles for longest distance. One part of the racing strategy is to in