Open core? Maybe free for non commercial use or a limit on the commerical usage? It won't be open source I guess but better than nothing if the intent is to push the tech and help innovation.
Vehicle dynamics is a fairly simple science except for modelling tyres. By which I mean (in steady state conditions) a mapping (Force, Slip Angle, Slip Ratio) -> (Lateral Force, Long. Force, Moments etc)
It's fairly complicated because Tyre's are made of rubber, so you either use finite element analysis which is slow, or some kind of (FD) approximation which can be fairly crap. Modelling the transient properties properly is doable, modelling the thermal properties efficiently is genuine "If we told you we'd have to kill you" black magic
