U Joint

I have had 2 front U joints go out with in the last 2 weeks. The first one lasted 500 miles and a lot of gear banging, but the second one last all of 20 miles. I have a hemi 4 speed that is bolted to a 340 that has been stroked 416 and is supercharged. It just plain flies. Has anyone out there had the same troubles? Please let me know, Joe