I think I need more cam

That sounds like a decent cam for a street/strip engine. A hotter cam will help you make power higher into the RPM range provided you have all the other things in place to work with it but it will not help the engine survive higher RPMs any better. Is the engine balanced? Do you know the flow characteristics of your heads? Will they even allow you to benefit from high lift? Which rods are you using? If you go much higher than 6000 RPMs it is advisable to go to solid lifters. There are a lot of things to consider when seeking high RPMs. And more importantly, is this a race car only? If it is a street car you are far better off concentrating your power below 6000 RPMs. Everything is a trade off. If you concentrate your power higher in the RPMs you will lose it in the lower RPMs. This is not good in a street car.