Hey Amazing -
Have you noticed there are 2 different casting styles on the 10-spoke wheels? LMK what you think about that. I've had 3-4 sets on cars thru the years, got them here/there and made sets, and finally noticed it one day...
yes, the FLAT spokes on the back (colloquially referred is "forged"), and then the ones that look more like "castings".
Don't get on me about the terminology as I aint a metals guy. They BOTH may be forged and/or cast -- but they LOOK different as you can see below
The "Flat Spokes"
The "Cast" Spokes
I was told (reliable source), but CANNOT prove except with my own experience, the flats were 1980-1981 and are a tad stronger (I have NO way of proving THAT either) than the castings from 1982 - through mid 80's when the wheel ended on M bodies.
Also, the 80-81 wheels, on the FRONT side, have a wider "Lip" (see below) than the others .. in fact its ~twice as wide -- so they have a DEEPER face. The 82 and up wheels, with the SKINNY lip, make this up so the offset of 4.5" is unaffected between the wheels. See examples below.
I use the wheels interchangeably .. BUT the 80-81 wheels REALLY polish well .. its like they are BRIGHTER when they are done. You only notice when you put them side by side.
My evidence? just watching .. i have had the same polisher do 40 sets for me. That isnt "proof" .. just an opiniion
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