Cost for labor on stroker build?

I have a 427 sbc in a G body, the shortblock was built Shafiroff Racing engines, 10/1 comp, AFR 220 heads, Hrc and I can guarantee you it doesn't make 650 hp. 575 maybe.
I also have a 512 RB w/Indy EZ, MW port heads 10.5/1 SRC, Indy MW intake for Dommie and it might make 650-675.
That's why I'm skeptical...
What's this 650 hp sbc in?
What's it run at the track? Should be 9's.