How much HP and what do you think it will run.

All I can say is if you have never had experience with 512 ci of torque monster , you are going to **** yourself the first time you stand on the loud peddle. Mine is 512 RB Indy EZ opened to MW Comp ,264/268 @50 630 SR. 10.5/1. Indy intake Thumper 1050 Dommie.
You guys are making me want to dig out my paperwork from all those years ago on my 440 build. We moved shops so not sure exactly where it is? But I was just north of 500CI on my build but I want to say less than 510? I bought what was then a standard stroker kit from Ohio. This was about ten years ago, maybe? I did not do anything fancy just the standard base line stroker kit. I can’t wait to see how this thread ends up once his motor has breath of life. To @Carnut68 point while there are certainly bigger stronger motors out there anything in the 500CI range will get your attention and sling you around the inside of the car! The feeling of just plain guttural power and torque is amazing. Love me some big block!