Once the installed height has been established you can use a spring pressure tester to determine the state of the springs. Obviously, this method of monitoring spring life by comparing pressures ...

A stock Chevy small-block valvespring typically uses a valvespring that measures 1.250 inches across. Most performance small-block Chevy heads use a valve-spring with an OD of 1.450 or 1.550 inches.

Check out the Erson Cams racing valvespring tech and some of their sound rules to follow. You'll find that valvesprings are more complicated than they seem.