Im not sure it was a NOS problem. They usually show other signs before this happens, or at least should be signs there now. Id look at the other cylinders and valves and see what you can find...
Your a smart dude, you will find the problem, and have it up and running in now time...
sorry about your luck..

[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]