Originally Posted by
6G72gearhead
Ummmm, no, nitrous acts primarily as an oxidizer, which means it can cause a lean condition, which results in heat, lots of it without a tune ( if using a dry shot especially). The typical signs of nitrous are holes burned in things, however that is not what looks like happened to your engine.
If the head gasket failed that could have pushed out that freeze plug, if it was already overheating this would have pushed out all the coolant in the head, while leaving some in the block. This would keep the block cool for a short time, long enough to bake the head pretty good.
The real question is what caused it to overheat initially, it probably has other cooling system issues.