big cubes and idle

I've searched the forums but need just a little more exact info, I know larger displacement mellows out larger duration cams, I'm looking for a hyd roller cam for a 496 that has street manners, I get the definition of manners is relevant, so in this case, my definition is the longest duration @ 50 cam that works best at mid 500 lift with with just a hint of lope at idle.
Thanks

I guess I should list the sweet spot, 2000 +/- to 6000 +/- rpm