Broke a torsion bar going over a speed-hump the other day. Fortunately I had a spare, just the small task of removing the broken one...
I cut the bar about 100mm from the block-end, and removed the broken section. A few hammer-blows to the stub left in the block, and it came out easily with mole grips. So far so good, just the arm-end to do...
A day of heat/hammer/penetrating fluid, and no result. As I was getting ready to drill it out, I tried using the drill on 'hammer only', driving an old SDS chisel shank. Result!! Ten minutes later, it was out, another ten and the new bar was in. Proper job!