Maximize the performance of your ProMaxx 300 head with this premium hydraulic roller valve spring kit, specifically designed for 8mm valve upgrades. Engineered for precision fitment and lasting durability, this kit delivers the seat pressure, lift capacity, and stability your high-performance Ford build demands.
Kit Includes:
-
(12) 100-6344 Steel Retainers – 7° design, precision-fit for 8mm valves, built for strength under high loads.
-
(12) 110-5033 Beehive Valve Springs – 110 lbs seat pressure, max lift .550", optimized for hydraulic roller setups.
-
(12) 110-7778 Forged Valve Locks – 7°, 8mm, precision-matched pairs for secure and accurate valve seating.
Whether you’re chasing street performance, race consistency, or engine longevity, this kit offers an easy, reliable upgrade to keep your Ford running strong at higher RPMs—without sacrificing stability or control.
Perfect For: ProMaxx 300 head builds, hydraulic roller camshaft conversions, and enthusiasts upgrading to 8mm valves.