The limited travel lifters have only .020 plunger travel, and take a .012 to .015 preload, only leaving .005 to .008 for the plunger to bleed down and lose lift. The standard Morels have I believe around .060 to .070 travel, and take a .035 preload. The limited travel lifters require roller rockers to get proper adjustment. They are better suited for aggressive cams with high spring pressures.