Interesting article about Billet vs. Cast wheels

[Super Bleeder!!]

Originally Posted by FFPerformance

But, to stir the pot , what about the material differences? A cast alum wheel is weaker than a billet version even if it's the same alloy. Most good billet pieces will be forged and therefore stronger. What does that mean? From some research I have done over the years, a stronger wheel will have less blade deflection, you would be surprised at how much the fins bend at full load, and you will have a performance gain from the added stiffness. What people should be talking about is the same wheel made of Titanium and see what happens.... ;P

$.02
-Bob

I have no background in manufacturing so take this with a grain of salt; but from what i know, a forging is strong/desirable because of the compressive residual stress near the surface which is manifested during the forging process. Once you start cutting into that surface and removing that layer, it no longer has the benefits of a forging. It is now a metal thing carved out of a larger piece of metal.