408 hyd roller, too much spring pressure?

They should, afterall, they are China slave, sweatshop heads..
Yes they are chinese heads, thats why I bought the bare castings not the assembled heads. I've used the Edelbrock heads in the past - mediocre valve job, stem heights were all over the place and the castings were pretty rough in comparison. So once you add the cost of a good valve job the price difference becomes fairly substantial. By then you might as well spend the bit extra for a set of Trickflow heads - which would be wasted on a mild 318.