lowered shortbeds on stock wheels?

[Tony_SS]

Originally Posted by SCOTI

But if the materials are different (15x8" steelie vs. 20x8" aluminum wheel) there is a mathmatical difference. To me that has to be calculated & not just assumed.

Yes, the mathematical difference is that the weight of the wheel (rotational mass) is moved out 2.5" further from the center. Even if the materials are different, it does not matter in regards to rotational mass and moment of inertia. Like the engineer said, its where the weight is.

.. but since most wheels concentrate the bulk of their weight along the outside (the hoops that hold the tire), MOI calculated at the outside edge is a decent approximation.