When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The size of the run wouldn't have been a big deal since they are cast and they likely would have ran extras. The fact that they also had 16" forged options like 7 slots available at the time makes me question why they would use a standard cast aluminum wheel on such special car. Like I said, "I believe" but I realize that could just be wishful thinking, lol.
I think you're in the wrong thread. LOL Although yes the tooling used to make the aluminum D90's could be used to make them in Mag. Aluminum and Mag both cast the same and have identical shrinkage factors although any of the mag variants of the CupI's and speedline 993 wheels used different or modified tooling increasing web thicknesses to gain strength. A stock 9" cup I weighs 26 pounds. the mag version weighs 20 pounds by all rights the mag version should weigh 17.4 assuming the same tooling was used. I don't recall what a 9" D90 weighs I believe it is around 20 pounds so depending on what would be needed to satisfy Porsche's over engineering it might save 5 pounds or less per wheel. It might have been worth it but the weight is essentially the same as the mag cupI's which I don't believe were brought to market until a year after the C4 lightweight was made. It might have sufficed and still retained the stock look for a select few cars.