[DavidNJ]

As part of complete weight loss program, an aluminum block is a key part, saving 60#. To really take advantage you would also use a lightweight crank (10-15#), lightweight rods, pins, and pistons (2-3#), small diameter damper (2-3#), lightweight clutch/flywheel (20-30#), and maybe some additional lightening machining. You can probably get close to 80-100# weight reduction, most of it off the front wheels.