There’s really no such thing as a “tune” for nitrous. Nitrous is completely stand alone. It doesn’t care what you have done to your car. Any car that is planning to have nitrous added to should be tuned prior to the N2O installation. The nitrous itself is tuned by changing the jets. You want to maintain the same AFR that the tune on the car is making prior to the installation. (or sometimes a little richer)