Cracked pistons

sorry to hear .
My sub assembly and RZ were built same time at same engineering and so far still no issues with mine under really hard racing . My advantage is I had mine mapped perfectly from the start and my team mate in our trofeo racing is the guy who wrote the software . Also my compression was 10.5 to1. Not sure what yours is .
I think the hardest part of any engine transplant is having access to someone who can map properly .
In my past (1998 - 2000) I broke three twin turbo 12v motors from bad ignition timing . All had cracked skirts until I finally found some one to map the engine properly and lock in fuel and ignition parameters that would not create problems .
Marc really sorry to hear of your woes .
By the way did you see on the short clip how immensely faster my 3.7 is than 3.0 12v on the race track on the straight . ( pity I could not stop as I still had all the gravel stuck to my wheels from the farming expedition on the corner before) .
I still swear by the reliability of these motors if they are warmed up properly ( fast idle) , not overevved and good timing .
Marc pm some pics