It was a stock shaft I had shortened.
On street tires............it spun hard to 150 feet , then hooked and twisted the shaft in half...............about 18 " in front of the pinion yoke.
It had a fair amount of street miles , but first trip to the track , it had enough.
It came from a big block / four speed car ( 1966 Cyclone ) and now had a fairly tame motor and an automatic that was foot braked.