Got my valvetrain tightened up, but have yet to get the rest of motor back together. Is it bad for .480-.490 cam lift to set on one valve all the time. I have turned the crank a few times to avoid the prolong pressure on the lifters and springs. I know they are designed to withstand it,but since there hasn't been a break-in period I thought I might be doing damage to the cam by hand turning the crank pulley. Should I not worry about turning it or loosen the rockers>? ..thx

 

RichRad,

It's good that you are obviously understanding the systems at play, and are and contemplating the possibilities. But, you're worrying too much.

If you installed good quality springs, they would not take a "set" for years. Cheap metallurgy, poor heat treating and annealing, or poorly wound or ground coils could "set" as you describe, but they wouldn't last long in an operating engine either.

What's perhaps more of a concern (and a minor one at that) is that you are possibly forcing out the oil in the lifter body and assembly oil whiule it sits. Then again, the factory built thousands of LT4 engines with more lift, and let them sit for months on pallets, in vehicles, and on showroom floors, and still warranted them. I've not heard of common valve spring failures on them, other than the customary complaint of weaker than desired factory springs in general. They have about 110# of closed seat pressure, and I don't recall the spring rate, but it's closer to decent aftermarket springs, and I seriously doubt they rotate the engines while in storage.