What cam should I get?

Well I talked to a friend of mine that has fooled around with muscle cars and told him what I wanted to do to my ride. He said that I should go with what I know will sound and perform good and that is the Mopar "Purple Shaft" cams. He also reminded me that I have a 4-speed and can go a little wild with the cam options.He helped me install a Mopar cam in a 383 Charger I once had. So I bought a 238 duration @ .50, .474 intake, .474 exhaust cam. It has 34 more duration @ .50 and 54 more lift than the cam I had. So I fired it up tonight and DANG IT SOUNDS GOOD! When I fired it up I let it run 2000 rpms for little over 15 minutes, fooled with the timing some and took it for a test drive. I didn't dog it but could tell that she wanted to go if you know what I mean. I think I picked a good cam like I did before for the 383. I was like burning myself out trying to pick a cam and got tired of looking I guess. How long do I have to wait before I can let it roar? I can't remember if I took it easy for awhile on the cam change on the 383 or just gunned it. I will change the oil this weekend. Thanks everyone for your help!