A virtual Dyno said this...

TT5.9mag said
If you can tune it, I could see a fairly stock cammed magnum with a 200 shot getting to 520-530. How long will it live there, depends on if you can tune it.

Edited to add;
I have a magnum crate that I bought from westech that was used as a dyno mule. With a small comp roller cam and an rpm air gap, headers and a 750 it made 365 so it’s not too far of a stretch to 530. Maybe not at the wheel though.

I was thinking my setup was close to a 380 crate pls 150 HP equls

MOPARMAGA said
High doubts with those carbs and that manifold.
But give it a shot , id like to have a new opinion on that stuff.

I'm aware that single 4 can easily out pace,I may be more willing to use the duals if I want more eye Candy.
It depends on what the engine pieces look like together