You'd imagine it to be of the same spec as those used in touring car motorsport....however its not always(infact rarely) the case.
If your not sure on what you want/are getting ask for more details.....valve size and material,combustion chamber volume, port size/volume and finish, valve seat angle(s), cam lift and duration, valve spring(s) rating.....maybe its been on a flow bench, ask for the results. Then post em up and the folks who know on here will be able to tell you what your head is good for and what it aint, providing the details are correct.
Job jobbed.