The lifters appear to be in perfect condition. Any reason they shouldn't be reused after sitting 25 years? I haven't mic'd the cam yet but it looks great as well.

When I last drove it, I thought the valves were floating a bit earlier and sitting without the rockers loosened doesn't help. So I want to check out the valve springs. Does anyone know what spring pressures I need with the old 509 cam?

I noticed the inside of the engine - the lifter valley and under the valve covers is black. No sludge or anything, just black. The PCV valve looks fine. Is there anything else I should look for to explain this. This engine always ran really well, better than others with the 509 cam that I knew of. I changed the 20w50 VR1 every year with well under 1000 miles on it.