rebuilt in 08, with ranger roller and new hyd lifters. one lifter clatters randomly. 5-20w syn.oil greatly reduced it. as oil gets dirty, clatter . is it the lifter moving up and down in the head ,or just a collapsed lifter . i am interested in converting head over to run solid lifters on ranger roller cam . is this a worth while performance upgrade? i dont care about valve lash noise and i think this mod could add some pep? i will go turbo soon.