Zex Nitrous kit Spark plug Question

I have installed right now denso iridium plugs are these good on a zex wet 55 shot nitrous setup.Running it on a B17 MOTOR

And what else should I check or change so I dont blow the motor.My timing should be at 16 degrees and should be running 91 and better octane fuel.

Is there anything else that I should do before I spray.