Treaded Vehicles Budgets and Special Rulings

So I’m relatively new to PRS and I’m looking to build a treaded car. I know its not optimal and that is probably a bad idea but I wanna have fun with it so lets just ignore the practicality issues for now. I noticed in the rules that there’s a 500% budget increase for walkers and shufflers, and I wanted to know if treaded vehicles fall under that. I also heard at a recent race something about there being a 200% increase in budget for a certain type of car, though I cant remember if that was for treaded vehicles or not. Either way, id like to know if there is any sort of special rulings for Treaded or partially treaded vehicles including those beyond budget if anyone knows.