Eta block with "i" head?

[rs4pro3]

the 11:1 euro eta had that high cr ratio becuase of the pistons, I possibly have a set of the rare birds coming my way, but not positive yet.
Halston the bently and other manuals list what the serviceable limit is for the m20 head, you can shave down to this thickness without having to get an adjustable cam gear, any more then you have to adjust the timing.

[mikeedler]

on the bottom side of the head(mounting surface) is an indicator that is milled into the head. I am not sure what it is in mm but, I told them to mill it to the indicator.

what euro eta motor is this with the 11:1?

[rs4pro3]

pre 5/85 525e, the pistons have a domed top.