whats so rare about the aluminum 5.3L? didnt alot of gen 4 trucks come with that motor? just asking because i have a alum 5.3L in my 82 c10 and would be cool to know i have a rare motor. its stock but runs strong has 10:1 comp ratio 799 heads 30# injectors 87mm tb, its rated at 315hp and 338ft-lbs of torque. im very interested on how your build goes so keep us updated.