MOREL LIFTER SET - LS - PRO SERIES - HYDRAULIC - 5206 The performance hydraulic lifters are made from a billet body with a clipped axle and have 7000 RPM capability. These lifters have .120 plunger travel and have an 80% fill rate with the test oil. These lifters have a .750 diameter roller wheel. Recommended spring pressures are 100-200 lbs seat pressure and 280-400 lbs open pressure.