Disappointed in my 383 on the Dyno

It’s fun, but not panty dropping fun which is what I was looking for lol. I have other things to fix on the car but I would like to have a plan for the spring when I can get the car back to the Dyno
I hate their cams and their heads need just a lil finessing.
Streetable 480-500 hp is what I'd expect a
"panty dropper 383" to put out , at the minimum .