Russmall, I had the Hacker A50-16S in my Angel 50s. I was running it with a cc hv85 , apc 16/10 prop and tpx 5000 6s batts. All I could get was about 1000watts. Not enough for me! I now have a Scorpion 4025-12 in the Angel. Hope you fare better with your setup!
I agree with Mike on the motorcalc numbers not being accurate. I also have a Axi 4130/16, it also out performs the Hacker.

Dave.