Done it, and totally hoped for the physics part of it. 1 pound of Rotational weight is Equal to 3 to 4 pounds of Dead weight.

So 60# rotational = about 180# to 240# Think the ratio was more like 1 to 3, its been awhile.

Sounds Super, doesn't it.

Real world for me, it was Pound for Pound whether it was rotational or Dead weight.

So Why was that? I know!! Its because the car has enough time to accelerate in the 1/8-1/4 that the physics effect don't have much effect combined with the acceleration rate.

Now, hang that same 60 pounds on the Crankshaft, Different story.

So with your change maybe figure .06 as in the Old rule of Thumb. .1 for every 100# and even that is just a, well old rule of thumb and not a exact science.