I bought a 2000 celica gt got an oil change/ tuneup and then the motor blew 1) dont know why? It had issues apparently. My dad got a motor from the junk yard for the cradle and block and i bought new parts rings pistons rods oil pump etc so he could make a new good one from the two but as he was building he noticed the oil pumps are different the new one is smaller than the one on the junkyard block.2) dont know why? The engines look alike cant see any other differences so far but anyone know of more i can expect? And what could be wrong?