I don't know about the euro-izing, but the 300HP euro only applies to non-cat (RUF) 560s made after 9/87. The cat model (KAT) after 9/87 was rated at 279...which most of them were. I think it was 89 where you could no longer get a non-cat version. So if that is right, then there would have only been 2 years of 300HP 560s in europe. The US models have 9:1 compression while the euros have 10:1. This is also true for the other engines too, like the 420 for instance which was rated at 224 and 231 KAT and RUF respectively as opposed to the 201 US HP.

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'86 420SE Euro
904 Midnight Blue, Gray Velour
Dad bought it new, now I own it.

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