I want to replace the valve springs on the motor I just purchased and I have a good idea of what I need, but I wanted to confirm with a few of the experts on here first. They're Dart aluminum heads and the cam is a solid roller with about .725 lift. I was thinking something with about 265-300lbs on the seat and about 750lbs when open. What do you guys think?
Also one of the oil seals failed (I pulled off the valve cover and there was teflon and pieces of metal sitting in the valley of the head). I pulled the manifold and oil pan and it looks like everything stayed in the head, so we got lucky there. Can I replace this without removing the head? What do you think would cause one of those to break?