Speed master spring issues.

To further the point, if you are using the same valves, keepers, and locks that cam on the SM springs, the Lunati springs will go in at the same installed height as the SM springs were. Those parts (plus shims) set the spring height. You have to detirmine if the SM factory setup is in the ballpark for the Lunati springs. As mentioned, a spring mic make it all a lot easier.