b12brothers

Hi guys,
I got something you got to explain : the NLA pistons 12010-13M22 are those Euro pistons and i did a little research and found a list, that those are interchangable with the 12010-73A22 (which we use in our E16S) and also with the 19M22, 11M22,13M02 and the 15M02.
I found that strange that these pistons would really be interchangable.
I cc'ed a 73A22 and got approx 24cc so the pistons are not the same but listed as interchangable E15 pistons ?

Result:
Our S models got 24cc-pistons (like on the pic I posted before) with valve reliefs and 17,9cc for the head which makes a comp. ratio of 9,59:1.

The I-models got 17,9cc pistons (33M22) and 24cc for the head: comp. ratio of 9,59:1.

What is this did they put all the parts in a box shook it and voila an E-engine and so on...