Yes this is a ray cast car !
The vehicles models are free to use, I downloaded them from various sources, at least free to use for non-commercial projects.
You can find the different links inside the credits/ directory.
To get an overview about the vehicle parameters, the best is to open the configuration files which are located inside the vehicles/ directory ( .xml files ).
Basically, absolutly no cheat is used like applying additional torque etc... The only thing is that the center of gravity is maybe a bit lower than in real life, but it could be higher it's just to make it easier to drive without a racing wheel and analog pedals, which i haven't plugged into the demo.
The tire model in the demo is a Pacejka like, but I also use a custom tire model for asphalt driving and another one in development for driving into every kind of ground surface where you can sink into. That will not be ready before a while !
The whole model is not yet complete, I'm currently working on LSD and locking differentials with locking arrays, and a component based system with an editor to build anything which has wheels. Additionnaly, there is a lot of work remaining for modeling different kind of suspensions, a better engine modeling, aerodynamic, etc... a lot !
NewtonDynamics wise, the technique is quite simple, some rays are fired from the suspensions in their direction. I made a custom joint to apply suspension constraints and tire lateral and longitudinal constraints. I use forces for gravity effect ( vehicle, fuel tank, etc.. ) and aerodynamic drag. A treecollision for the ground, with different ground surfaces per polygon.
Well it's hard to explain in details what I have done, but I'm ready to answer any specific questions if I can.
What I can do is give links to reference materials I have been using :
Brian Beckman's Physics of Racing
[url=http://www.amazon.com/Tire-Vehicle-Dynamics-Hans-Pacejka/dp/0768017025/ref=pd_bbs_sr_1/102-7954284-5210553?ie=UTF8&s=books&qid=1190212643&sr=8-1]
Tire and Vehicle Dynamics, 2nd edition by Hans B Pacejka[/url]
Newton again has been really easy to use, and very stable which is a big pro for this kind of simulation. However, what about soft bodies, particle physics, is it a planned feature for 1.6 and is there a planned date about it ? I know it's free, I know it will be ready when it will
I'm just asking since i'm curious about how the development is going.
And don't take me wrong, we are all busy with a lot of things so I any answer will be ok !