what are the usual damages casued by running too much nitrous ("100 shot") on a bseries motor?

why i ask? someone i know has jdm b18c (c5) , and i want to purchase the head from him, he recently ran '100 shot' of nitrous, and blew something? i just want to know what to look for when i see the head, etc? if it's worth buying.

 

Usually, Nitrous damage occurs at the bottom end (Crank, Connecting Rods, Pistons, Block damage). Because of the stress of the added horsepower. I'd say your buddy isn't too smart running a 100 shot on stock internals.. Make sure you check for oil where oil shouldn't be. Look for signs of excess carbon or scorched metal. Personally, I'd be real apprehensive knowing that engine's background and I wouldn't make the deal myself. Plenty of Honda parts to go around. Oh, also check for chip marks or metal to metal contact with the valves...