Dart BBC 31263444S 4.5" BORE 9.800DEC .904 LIFTER w/piston squirters and raised cam tunnel. i have 2 one needs a hole at .060 over or a sleeve. one needs .030 over, both are very low hour piston failure blocks. one 1.5 hour, other 2.5 hours run time. OBO must sell. Private sale. sorry no pic available at this time.