euro 944 8v compression

[914efi]

Do the early euro 944 engines have different pistons or heads for their higher c/r? Any idea on octane requirement for these engines?

Thanks

[Techno Duck]

Different pistons were used. The euro pistons are completely flat ontop with reliefs cutout for the valves. This gave them 10.6:1 compression. All 944's from '83-87 had 9.5:1 compression. '88 had 10.2:1 compression and as a result slightly more HP.