As Ron suggested, I did just that. I had a lengthy conversation with BBS domestic distribution facility down in Georgia on topics discussed in this thread.
Not sure of your basis for thinking this is ok.
First and most important directly from BBS, subjecting either the “cast flow formed” standard FGT wheels (Germany) or the “forged” optional FGT wheels (Japan) to a powder coated 400F bake cycle WILL compromise the T6 heat treat of the aluminum alloy used to manufacture either wheel. BBS continues to field this type of question very frequently. They review many rims returned to them for a warranty claim and see the effects of this heat cycle all the time. Their recommended analogy is to subject the wheel to the same thermal environment you would to an automotive hood.
The forged BBS wheels are made from a 6xxx series aluminium alloy, tempered to a T6 condition.
6000 series aluminiums are alloyed with magnesium and silicon, are easy to machine, and can be precipitation hardened, but not to the high strengths that 2000 and 7000 can reach.
-T6 Solution heat treated and artificially aged.
http://en.wikipedia.org/wiki/Aluminium_alloy
I realize (as does BBS) the application the wheel is subjected to also matters. Thus,
if an owner is making a table with used FGT rims or the car is relegated to a “show car” only status, it would probably be ok to subject the wheels to this thermal cycle. But Ford was very careful as was BBS in supplying wheel material strength characteristics intrinsic in either of these two wheel options on a supercar which could highly stress the wheels in its intended driving environment. And since this is viewed as a safety issue, due consideration should be made. Any welding or re-bending of a damaged FGT BBS wheel will affect structural integrity and just should not be considered, according to BBS. Yes, you can claim they just want to sell new rims to replace damaged units, but my feeling during the discussion with BBS was certainly not a financial one, merely that of safety. But again, every owner can do whatever they want in this regard.
Three questions:
1. Does anyone have a recommendation of a source to get wheels refinished to "exactly" duplicate the factory quality?
Answer- Unlikely anyone can exactly duplicate the OE BBS process. It is a 2-stage process with a light base coat applied, then a very thin translucent high solids silver layer and a topcoat applied. The depth of sheen is achieved by the light basecoat shining thru the thin silver/top coat. The BBS process is very specific and only applied to new wheels which they make. They have no capability (or interest) in reshooting used rims.
2. Is the finish on the inside drum and rim of the wheel the same as the outside spokes and rim? I am colorblind, so can't tell if there is really a change in "shade", and there also seems to be a slight change in texture?
Answer- Sorry I forgot to ask this question, but I would think BBS would not go to the trouble to apply two different colors to the rims. They might, however, vary the thickness of the silver layer to change the transmissivity of the base coat through it to give a slightly different color.
3. I know there is a Thread on here concerning an effort by someone to "match" the color of the wheel paint in a touch-up format, but I can't find it. Can someone give me a link to it please?
Answer- There has been a number of previous threads on the topic of power coating and painting FGT rims. BBS said a good automotive paint shop could probably come close to matching up their 2-stage process, but that’s as far as they went on recommending any painting process. I do not have a link to any of the old threads.
Interesting question and I believe now after talking to BBS directly I would agree with your premise that “it would not add value and most likely be a negative factor.” I believe knowing a set of wheels on our cars has been powder coated with the attending temperature drying/fusing cycle would most definitely be a negative attribute to the sale.