Rhoads Lifters 22-1-15000-8 Variable Duration Hydraulic Flat Tappet Lifters

Using Rhoads' exclusive patented variable valve timing technology, these lifters reduce valve lift and duration at idle and low RPM, then restore full lift and duration as engine speed climbs — giving you the best of both worlds in a single valvetrain component.

Key Features:

• Patented variable duration design reduces lift and duration on the low end and fully restores them at higher RPM
• Increases low-end torque, engine vacuum, and idle quality when running aggressive performance camshafts
• Anti-pump-up design supports maximum high-end RPM capability
• Lift is reduced at idle by approximately .010" to .020"; duration reduced approximately 10–15 degrees
• Full lift and duration restored at approximately 3,500 RPM
• Typical manifold vacuum increases of 1–3 inches at idle with performance cams
• Made in the USA with high-quality materials and precision workmanship

Rhoads Variable Duration Lifters are ideal for high-performance street, marine, oval track, and strip applications. They allow builders to run a larger, more aggressive camshaft while still maintaining the low-end drivability, engine vacuum, and idle quality required for street use. These lifters are manufactured under U.S. patents 3921609, 4524731, and 4913106.