Forged aluminum is not lighter than cast. (archive)

I looked at both types before deciding to go with the original and more expensive Motorsport wheels.
The main difference is the BMW Motorsports are forged and stronger, but not lighter, than the cast knock off's.
I have not weighed the knock off's, but forged aluminum is a higher density than cast aluminum. Thats what makes them stronger. Since both are equal dimensionaly, the forged wheel should weigh more for the same size and design wheel(18 x 8).
However forged wheels in general are often lighter than cast wheel because the strength of the material allows less to be used, and therefore be lighter than cast.
Another big consideration when I purchased was that cast replicas where only available in one size, 18 x 8, and original where available in 18 x 8 and 18 x 9.5. The larger forged wheel is even heavier than the smaller one.
Be sure you know what you are buying, as most original wheels are staggared size front and rear and knock offs are the same size all the way around.
Another indicator is the presence of an M logo near the center of the wheel on original BMW Motorsport wheels.
Much of this has been discussed here before, if you care to reserch the archives.

One is OEM and the other is a knock-off. The OEM is lighter and more expensive.

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Re: Forged aluminum is not lighter than cast. Allen 20:16 7/02/2001 (0)

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