Time Lapse Lapping Cylinders
 

The 1970 had no head gaskets / flame rings. So... gotta make sure the sealing surfaces mate properly.
This might be a boring video if it wasn't time lapsed!!! :)

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I thought I was the only one to think of doing that.

The Mahle cylinder sealing surface is not flat (tapered by design) on cylinders with no gasket/ sealing ring so lapping them is actually counter productive. Interesting idea though.
It was done on the 2.0 cylinders but those have an entirely different design.

Yeah, I hear ya Henry. But I didn't lap them flat. Just knocked down the high spots that showed with the Prussian blue. Just a little rub a dub dub to get them back in line.