A retune specifically for the nitrous would be needed. Nitrous is some volatile stuff and one thing going wrong (loss in fuel pressure, safety switch failure, spark plug fouling, etc, etc) could leave a hole in the engine block.
I've watched nitrous being tuned on a focus on the dyno. With the base I/H/E tune and lots of extra fuel added and timing pulled the A/F shot to over 18 when the nitrous hit; on 93 octane and Autolite 103 plugs. I don't know how anyone can confidently run nitrous on a stock tune or other tune not for the nitrous.