Just when I though I had it all figured out...
Only 1 fuel injector and 1 NO2 injector? Kaotic?
I assumed the Contour ran multipoint injection and so would have 4 fuel injectors - one firing into each branch of the inlet manifold just before the cylinder head (like on my Mondeo inlet manifold). Therefore assumed the wet NO2 system would have 4 NO2 jets – one fitted beside each fuel injector as suggested by OhSigmaChi.
I wasn't really suggesting that it would 13 seconds for the NO2 to reach the cylinder in a dry NO2 set up – I'm sure any delay compared to the wet set up would be relatively short but perhaps significant during gear changes in ¼ mile situations.
If the shot size 35, 50, 75, 125 etc is related to the size of the NO2 jet (or jets) – then what difference does the jet size make as to how long the NO2 is fed into the cylinder for?
Any ideas on the spark plugs question?