Comes with short .115" of travel. Oversized Diameter (0.8435" - 0.844"). Standard size is 0.8420" to 0.8423" OD. New revolutionary design with 0.115" of total travel vs. a full travel lifter with 0.200". These hydraulic lifters will increase RPM by decreasing valve float and valve-train harmonics while maintaining a quiet engine. The travel reduction reduces the amount of oil that is required to fill the inside of the lifter which reduces oil aeration inside the lifter on steep; fast action high lift camshaft lobes.NOTE: when oil aeration is present inside the lifter; the pushrod seat drops when the lifter rolls onto the front cam lobe ramp after squeezing the aeration down thus creating a noisy poor performing lifter.Feuling short travel lifters should be set with 0.065" - 0.070" of pre-load and with the normal engine growth from heat will put the operating lifter pre load at or around half travel.Machined from a steel body and designed to exceed the needs of large lift camshafts and higher valve spring pressures with a slower bleed down rate. RACE SERIES lifters maintain proper oil flow to the top end; increase engine RPM; valve-train stability; decreasing valve float promoting maximum valve lift.Feuling recommends Race Series lifters for engines running higher than 185 Lbs. valve spring seat pressure. FEULING recommends the use of a high volume oil pump which will result in quieter; better performing lifters. Race Series lifters are compatible with either FEULIN