For the OP, agree as several have posted, a suitable cam in the range of 240 intake duration @.050" should make it a good street engine. With 500" you should have plenty of torque with either a SP or DP intake. No real need to change it. The CR may be a touch on the high side so avoid a tight LSA cam and give it a gentle timing curve if needed.

For Demon, a cam in the similar range of intake duration or a bit less shoule do it. There are some good posts in the archives by Andy F on cams for manifold applications... have a look. I believe the ".525" MOPAR mechanical flat tappet works quite well in this application.

Link to archives: http://www.moparts.org/Tech/Archive/bb/Lobe.html