If you buy a stage 3 set up off Stu, you get the actuator, the chip and injectors with fitting instructions. You then set your boost and fueling to what the instructions tell you to. The chip has been developed over years and has a safety margin in the ignition and fueling to allow for deviation in different engines/fuel quality etc. If you have it mapped, it will be tailor made for your engine spec without needing the same kind of safety margin.

My statement was meant to indicate that only someone like Stu with experience in varying types of engines and secifications will be able to give you a very rough set of figures.

For example, if I knew that dependant on spec most ZVH engines will comfortably run between 10 and 18 degrees at 25 psi boost at 5k rpm, I'd tell you to run 6-7 degrees as a safety margin. Without pushing it to the point of det, you won't know what figures it will run safely but you can have an educated guess.