Mods: Supercharger @ 13 psi Ported Heads Cam Meth Injection Full Exhaust Oil: Castrol 0w40 A3/B4 Euro Fram Ultra Filter Fuel was 93 pump, and for one tank it was a 50/50 mix of MS 109, but that was only once. Stock short block (crank, rods, pistons), pushing it pretty hard power wise. I did some airport racing during this change, with a lot of WOT pulls. No new parts were installed between oil changes. If its not a bearing, what is it? I thought bearing due to the stock bearing contents initially, but I don't really grok how much would be in the oil if the bearing was going bad TBH.