One of our local tracks switched to AHRA here a few years back, so nitrous is acceptable--I used to use the Y connection deal, but the last few cars I've done have gone to a separate 4 gallon cell, pump, lines, and regulator to feed the fuel solenoids, even went with a water-alcohol injection system on one car to engage with the nitrous and cut down the amount of timing retard used on the big end. I'm also a firm believer in a Nitrous Timer Box and a Timing Retard Box! With the correct pieces and components in place it's both fast and safe when used in the amount the rest of the engine is designed for!!!!

Don't do like some and put a 250 shot into a stock bottom end engine!!!!!! ---and please don't ask how I learned this!!!!!!