How is this cam for 470

Thanks for fixing the writing Gene (or Gene's wife).
Well, for me, the object is to spend what you have to in order to accomplish your goal. Preferably only spending once. Maybe you build a lot, maybe you don't. I know nothing about you. Based on the parts list and questions I can't tell where you're coming from. Not anybody can run fast. I know plenty that spend five times over buying and trying and even with the big rollers they can't run numbers. Regardless it comes down to simple physics. There are very few professionals that will get past 295 on factory heads and those that can flow that well usually crack fairly quickly. So I think the 285 is realistic at least.
Simply put, there's not enough duration at the lifts the hydraulics are made with to flow enough air to do what you want with those heads. At least not in my experience. Engines are air pumps. Torque or horsepower they have to have airflow. Make all the torque you want. It's horsepower that will win races at the track, at least in a properly executed effort.