I currently have a Crane cam with 226/236 duration and .450/.450 lift at the valve. Recently I had a lobe go flat so Im going to get a new cam, but I want to get a bigger (and better) one. Before the cam went flat, it would start to come into the powerband around 3000, made good power to around 5000, and would rev to 6,000. I would like it to be able to rev to 7,000, and I would like the powerband to be a bit wider as well. Im thinking about going with a wider lobe separation angle and I know Im going with more duration, but Im not sure what numbers to go with. Im thinking about a crane cam with 252/252 duration and .450/.450 lift. Should I get some stiffer valvesprings?