Hello, my Evo X had recently had a spark plug nightmare in which my Ngk Iridium oem plugs had its electrode melt due to pre-detonation. Had the head sent out for valves and reseating and had order new connecting rods and pistons heads the whole nine yards from the dealership. Luckily my cylinder walls checked out and turbo was saved as that electrode bounced up mercilessly in my engine. My question and the question that seems to confuse my local dealership or stealer-ship for say is the pistons provided are stamped 330 - not 331 as my pre-existing pistons were. Does anyone know if this is just a different cast marking same piston ?