converter blown in half at the weld

just put a fresh glide in a Mustang. purchased a used converter form a YB member that had 15 passes on it.....anyway got it in last week hooked up the new electric shifter and decided to see if it worked down my 1/4 mile long driveway.... Road was wet and a brand new set of slicks so i was very easy on it. I shifted to high and if shifted great. stopped and stuck a 3,000 RPM chip in the switch to see if it worked. Before i got to three it was like it went to neutral...looked under the car and fluid was everywhere. Converter busted in half at the weld. Anyone ever had this happen. My trans guy has never heard of it and the converter co. has never heard of it either. Its a PTC converter. 630 h.p. car. Got the same set up in my 1,000 h.p. car and never had an issue....