Is it possible to see information such as horsepower and torque of cars in GRID 2?
Solution 1:
Unfortunately not - the only vehicle statistics shown by the game are the overview statistics you've already mentioned, which are shown when selecting a car;
Solution 2:
You can, but only by using a mod program to inspect the files on PC.
You'll have to grab the CTF Editor from here.
After downloading it follow the instructions in the readme to extract, and run it.
In the editor, switch to the Other tab, and use File -> Open to browse for ctf files located in the grid 2/cars/models/xxx (ex: for mustang mach 1 xxx = mac) folder of your Grid 2 installation directory.
Once the file is open you can scroll to power, for example, and right click the value to see the power curve values. I believe the values are in SI units. (rad/s, Watts)