[Too Many Projects]

As Freddie said, a 2 bolt block is fine for street use. Find a 2 bolt 512 cast block and they are the same as the 4 bolt. I bought Freddie's 427/390 engine last year for just this purpose. It is standard bore and with a forged crank. The cast cranks and low performance rods were the main reason 2 bolt engines blew up at high rpm, not any fault of the block. Build the internals properly with a 2 bolt and you won't have any issues.