[THEFERMANATOR]

If they're stuck in really bad, I like to cut the bolt head off and try and pull the head off that way. Then you can heat and cool the remaining bolt a few times to expand and contract the materials some a few times. Then use a pair of parrot nose pliers on the bolt sticking out and heat the block up and then work it back and forth a few times. Remember the aluminum block will expand faster than the steel bolt, and the aluminum will normally expand more than the steel to. By heating the bolt and letting it cool off a few times will stretch the aluminum out some and in many cases allow you to be able to work the bolt out. I have had nothing but broken bolts with impacts though, so I use hand tools for any stuck in bolt now.