Another “which camshaft” post

Here's my opinion that Oregon 2120 looks like a pretty sweet cam for your setup. I also run a six pack, I don't think going up in camshaft would necessarily help much because of your rear end ratio and factory exhaust manifolds. Those duration numbers at 50 look about right you may want to find something with a little more lift but realistically with the setup you have that looks like a really good cam.