[914fan]

As far as lightened flywheels you should not have any problem. Lets look at it this way. Some small 4 cylinder engines have flywheels lightened to 10 or 12 pounds. The flywheel weight affects cruising more than anything. Your rpm's will build faster with a lighter flywheel, however if everything else is still heavy then you have to ask what the point is. With a heavier flywheel you can cruise using less fuel. the heavier fly has more Inertia. It is important to consider all aspects of rotating weight. A good balancing job includes the flywheel, pressure plate, and associated bolts. If youe engine was balanced to a good degree a lightened fly can throw off your balance job. The weight of everything else (pistons, rods, crank) will compensate for a lighter flywheel, and you should see no problem. As I said I have seen many stret 4 cylinder cars running 10-12# flys.
A LMOI fly sounds like bs. I could be wrong, but if you remove weight from the outer edges of the fly it that not the same in effect as running a smaller fly. Say a 10 in disk lightened mostly on the outside is equivelant to a 9 in disk or therabouts. And you retain the abiliy to run a larger (more surface area) clutch. Again I could be wrong.