Hello, if I was considering a mild 470 procharger build. Say a street 650hp. Would I need an after market block to make this live? This would be a 99% street ride. The problem I have is no one offers a steel low deck block. (yet) What do you think?

I think a stock block could live fine at 650 HP. Aluminum main caps are becoming the preferred way to build a stout bottom end on a stock block. At 650 HP a sonic check of wall thickness would be highly recommended. It may take a couple core blocks to find a good one or you may have to sleeve a hole or two to get cylinder wall thickness where it needs to be.

As long as you don't get craze with timing you should be fine. good luck

I ran a stock block 400 with nitrous to make about 850 hp. I am going to use my stock block Magnum block to make about 700.

Turbos are much easier on blocks than nitrous.