You can use an 11mm nut on a 7/16 SAE bolt and vice versa. So they are the same size, within manufacturing tolerances, IMO. Perhaps Porsche used some "special" 11mm size? Kraftwork, true, the SAE needs to be at least grade 5.
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Gordon
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'71 911 Coupe 3,0L
outlawed
#56 PCA Redwood Region, GGR, NASA, Speed SF
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