Yes I might as well say it as it is.. my block has cracked, correct. And serious biip biiiip bip biiiiiiiip crap!!!!!!

It was on ARP stud/nut. Its the third or firth time I use them, but this time the car ran 4-6km .. tadaaa.. capuccino oil .. end of this season (well, the season was already over)

The evening these things where fitted, where discused with my friend, and helper for the evening, that I did use TOOOO much oil on the thread, and I do remember I was generous with the oil, and didnt let the stud, how do you say, "drip of" enough. After some research this COULD be the problem.
As said I have fitted these bolt before wothout problems at all... I even found out I actually torqued them down with little torque!!