Complete Single Valve Spring Kit

The Ferrea Complete Single Valve Spring Kit (KT4025) is engineered for high-revving VW 2.0T TSI engines, offering a significant upgrade over stock valvetrain components. The kit utilizes premium-grade alloy springs that undergo special thermal treatment, ensuring uniform load and stress distribution even under extreme racing conditions. This advanced design and material specification help prevent common stock valvetrain failures such as binding, breaking, and valve float, which can lead to engine damage and power loss at high RPM. The kit contains 16 Single Spring S10157 units, eight Titanium Retainer E11139, eight Titanium Retainer E11140, and sixteen Seat Locator SL1142. The springs are heat-treated and stress-relieved to dramatically increase their lifespan and provide the stability needed for high-lift, high-RPM racing engines. Ferrea offers a choice of four retainer types: Titanium, Lightweight Tool Steel, Steel, and Aluminum Magnesium, all CNC machined for superior strength and stability. The included seat locators are crafted from 4140 chromoly alloy with a hard Nitrided surface for enhanced toughness and wear resistance. This valve spring kit is specifically designed for the CBFA / CCTA Engines and is compatible with a wide range of Audi and Volkswagen models equipped with the 2.0T TSI engine, including various A3, A4, A5, Q3, Q5, S3, Beetle, CC, Eos, Golf/GTI, Golf R, Mk5, Mk6, Mk7, Passat, and Tiguan variants from model years spanning approximately 2005 to 2020. Always verify fitment with your specific vehicle's make, model, submodel, and engine designation.