QUestions on running nos!

ok, i've got this 50 hp wet shot on the way and i'm wondering what kind of boost spikes would be expected with this nos setup. i'm going to be running the sp63 with it which has the hks gt wastegate. does the quality of certain wastegates regulate the amount of boost spike you will get when you hit the nitrous? don't know that much about nos setup on turbos yet so any help would be appreciated! also, what kind of a/f ratios should i shoot for if i'm running 22 psi of boost on 93 octane and then hitting the nitrous. should i richen the fuel a little when i plan on running the nitrous.