Its most likely going to have very similar physics as 1. You gotta realize that more complex physics you have, more complicated it is to make content for it.
In rF2 offic cars come out every 3-6months, being quite extensively tested for the last few months of its developement. In AC or pCars, they somehow come out with 10 cars a month even cars that in real life have extremly complicated electronic differentials, dynamic dampers, torque convertors, brake systems, stability controls etc. It simply screams how fudged the physics are.
pCars 1 also hyped people before it came out only to disappoint everyone, pCars 2 is just history repeating itself...
Plus - pCars is going to have all sorts of racing, dirt, rally, ovals, circuits, steet cars, all over the place. That shows me even more how fudged it will be because you might aswell have two completely differend tyre models for lose surfaces. And that is just the tip of the iceberg.
I wish even rF2 had more realistic physics in many places, simply no other sim comes close. There are some things in AMS physics that are better, but overaly na-ah