Real value of ignition on Motronic 3.3.1

[valouweb]

Hello,

I am the happy owner of a 325iE36 With ecu 0261200413/623 (M3.3.1)
I would like to know the formula for real values of ignition advance (degree°) in Tunerpro, I do not want to break my engine.

Thank you in advance for your answers,
Valentin