[andy669]

Ok, I'm a little late here, but here goes:

I think an aluminum flywheel is the second best performance upgrade you can do to your Mustang. (the first being gears) The lighter weight of the aluminum means less overall rotational weight, but since the majority of the weight is on the outside diameter of the flywheel (ring gear) the aluminums usually have a higher Moment Of Inertia than their heavier counterparts.

I have track tested a half dozen different flywheel and clutch combinations ranging from 23lbs of total weight, up to around 45. In MOST cases, (not all) lighter is faster.

Andy