Like the others said, the tranny and diff ratio's will have a lot to do with it. How did you blow a 4 bolt main? The 350 should do fine. If you can find one cheap you can get all the power you need with rebuild. I'm currently rebuilding the 350 out of my truck and when I'm done it'll have 320 hp and almost twice the stock torque. I had to by new everything for my motor and I mean everything. It was still less than a crate motor. I have pretty much just made it 10 to 1 compression, advanced the cam shaft 4 degrees, and a few other things like new heads and such. I know that the newer bluebirds used Caterpillar diesels, and the bus I ride every morning is an 88 International bluebird, I definitely notice a difference when it's fully loaded even with the diesel, but a 350 should do perfectly well.
