This is the kart physics planned for Roas52's Karting, I changed a few things from @izhanm11's kart he sent me, and he is currently working on a final version of the kart. You can race around the original tracks from Simple Kart Tracks. Use the number keys to switch tracks. x to drift, z to boost, and c to use items. Please note that item boxes and the items associated with them do not work properly yet.
I recommend using Forkphorus if you are having any loading issues. There is no start and finish line yet. use the n and b keys to toggle debug variables