So if you were to build one of these engines to use on pump 93, what kind of compression can you get away with and still add boost? I know the Hellcat is 9.5:1. Is that about the limit ?

I use water injection on my TT383 and while I'm a ways off on my turbo 5.7 build, I plan to inject it as well. To me running pump gas + injection is the economical way to manage it.

I am not sure what others are running, but I am running a stock crank with drop in pistons and rods with about 9.78 compression. I am running about 10 psi with methanol injection. I have only been running with the supercharger for about a month, but so far so good.