Compression ratio limits?

Hi!

Can someone help me find the max. Compaction ratio of an petrol engine? I've already searched through all the books, but I don't know.

So. Our engines have 10.6:1! I had once built a VW engine with a colleague, which was 14.5:1. I still have a mind of some kind. Abe that was already hard on the border to the self-ignitioner. Idle sometimes had a small self-ignition with it. He went like shit, but he didn't feel so durable. after some rework, it is now. However, we also took the compaction down a bit.
What is the boundary between the foreigner and the self-ignitioner? I'm counting like crazy, and I didn't really want to build anything that I might regret.*gg* I'm swinging between 13 and 13,5 back and forth.
Who knows where to find it in the net?


Thank you
Ronny

PS.: Who disturbs error in the lower case, can buy me a new shift key! :-)