100 horse shot of nos for 440?

Here are a couple of sites to help with jet sizing.

http://www.robietherobot.com/NitrousJetCalculator.htm

http://www.dynotunenitrous.com/store/Scripts/Jet_calculator/nitrousjetcalc.asp

The n2o solenoid will want less pressure than the carb in almost every case with a reasonable jet spread. A regulator for the carb and separate regulator for your juice unit fuel solenoid is the best approach.