I am new to this electric stuff. I have a hobbywing 60a esc right now with a 8.5t motor. I am wanting to get a 17.5 for stock class. Can I run any motor with this esc or do the sensored motors have to be sensored in order to work?

You can run any motor on that ESC, but the startup quality is very hit and miss when using sensored designs on a sensorless controller. There is a difference in the way they wind them to take advantage of each type, and also the lower the Kv, or higher the wind, the harder time the sensorless ESC has to get it rolling smmothly. I have used Novak and Orion 10.5 motors on Hobbywing ESCs with only very minor cogging, but I hear often that 13.5 and up can be pretty annoying. Your best bet is to use a sensorless design to avoid any issues. I believe Hobbywing makes a 17.5, but it is likely not ROAR legal if that would be an issue.

thanks for the advice. I am a bit leary to purchase another motor for it if as you say people seem to have larger cogging problems with higher turn motors. Mine came with the 8.5t which I used in a zx5 and I had quite a bit of cogging going on. I will be running a touring car on indoor carpet with the new stock setup, which I would think any cogging would be even worse on a onroad car.