**600hp sbm block limit? Or is it bs!!**

Thanks Mad Dart for starting this thread (and all of your other inspirational/enviable build threads), you and everyone elses input has answered a lot of questions ive had about these blocks. I am still wondering a few things: Im kind of confused as to which direction to go with my engine. Currently, its a 408ci 360 block from 1975. I know its been discussed a bit but im still a bit unsure: is a magnum block on a level playing field with an older LA block strength wise?

Im thinking of picking a magnum block up from the u-pull it yard (b/c theyre abundant and cheap) and slowly building it with forged internals, H-beam rods, studding everything, and partially filling the jackets with block filler. From what ive heard the magnums cylinder walls are thinner than the LA, how true is this and would it be enough of a difference to want to stay away from the magnums? Id plan on running 800hp+ if i do go forward with buying a second block and building it up.