The torque values between fine and coarse threads is far different for the same clamping pressure.
A stud with coarse or fine threads at "BOTH" ends can easily be swapped out for a bolt but not recommended.
Most stud applications are of a course thread in the block and a fine thread for the torqueing. The clamping pressure is greater for a given torque value than the "same" torque value on a course thread due to the greater leverage of the finer thread.
I have seen a few heads come loose because they torqued the coarse bolt at the same torque value as the fine threaded end they replaced by using a coarse bolt loosing valuable CLAMPING pressure.
Dave Neptune