Roller Rocker Weirdness...(Long)

[chris91LX]

I put in my roller rockers a couple weeks ago and things were fine. Last night I had one of the nuts back out on me and I pulled it apart and re-torqued all of them again. The problem is that I noticed after I hand tightened the nuts down on the rockers, on cylinders 5,6,7,8 both rockers (intake and exhaust) would tighten easily with the wrench, compressing the valves and valve springs at least a half an inch. The weird part was that in cylinders 1,2 & 3 after the nut was tightened hand-tight, the wrench would barley tighten the nut more than a 1/4 turn and it was TIGHT. It just seems odd that 10 of the sixteen valve/valve springs would compress so much while the others didn't compress at all. A freind thought the valve springs may be tired but it seemes awful uniform for all of them except the ones in cylinders 1,2 & 3 to be bad. Anyone have any ideas why this would be? TIA