I've got that cam in my '85 d350 four door, 360, stock compression, stock intake, headers, duals, automatic, same gear.
Rough idle, poor low end, great at highway speeds.
So I guess I'd recommend a milder grind, or more compression, or try advancing it.
I degreed mine and set it to whatever the cam card suggested.
I guess it's been in the truck since '98, keep thinking I'm gonna change it one day!