Either way, the engine should be fine. It's still within the acceptable limit and oil of different viscosity is not going to harm it either. What would alarm me though is that the engine consumes so much oil. Check for leaks (could be from the head gasket, oil sump, collars of all sort, crank gasket etc). If there is no leak then perhaps the valve springs are gone (does it emit blue spoke under full load / heavy revving?). It needs to be taken care of.
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FERRARI RULES!!!