Alright, school me on stock roller cams....

from other sites I got this
stock 5.9 Magnum cam
250/264/110 installed at 119.
this makes the Ica to be 64* to work with 9.4 compression 360M engines
But ...... that also kills the Effective overlap, which with log-manifolds doesn't make much of a difference.
However, in a low-compression engine, you cannot afford that 64* Ica, and with headers, you would be sacrificing I'm guessing about 10 hp over the nose. SO
IMO, a better install would be in at 106. This puts the Ica at 51*, and increases the Effective overlap to the maximum possible. But yes, you will lose the idle-lope, while picking up a lotta pressure. Pressure is power.
In a true 8/1 engine, this install is predicted to make 15psi. Count 'em .. 15psi! that's a lot.

I cannot speak to the veracity of the 119 install, but several sites I visited are fairly confident about it, PLUS, logically, if you install that cam in an 9.4 Scr Magnum, the pressure would go thru the roof, probably well into detonation with iron heads. Even 9.2 is too much for a 51* install, with pressure around 165 at sealevel.
I don't have specs for the 5.2M cam
Jus trying to help.