well, I had gone all out and bought a Tomei head gasket for plenty of dough, thinking, well, seems like a necessary upgrade. I just got my Nissan RB26 engine overhaul kit today though (all basic gaskets and a toothpaste tube full of, uh, gasket gunk?), which also includes an OEM Nissan RB26 head gasket. Now I'm looking at this thing, and it's no paper job like on many a stock car. This looks like a solid chunk of metal too. So what gives? What's the real difference? Why does the OEM head gasket "not cut it", when it's a pretty solid looking metal head gasket?