I don't know the rating, but those look like the same type of wheels I had on my 70 Dodge Challenger. I didn't have a very good experience with them. The hub cracked out of the center of the wheel at the bolt hole circle and the tire and went bouncing down the road past the car. Not a good day for me...
I hope its not the same brand I had (Ansen I think?) because I heard from a lot of other people with similar stories about that type of wheel.
I don't know the rating either... and when I took on of my tires off, I noticed the aluminum wheel looked cast on the back side it was rather massive are far as material goes. They definately did not skimp on the amount of aluminum.
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