Manley Performance Valve Spring set - 2002-2014 WRX, 2004-2021 STI, 2005-2012 LGT, 2004-2013 FXT
The Manley Performance Valve Spring Set has been designed to accommodate high-lift cams, and to allow users to surpass OEM rev limitations when power levels have been increased from built motors, larger turbochargers, aggressive cams, or ported heads. Basically if you plan on drag racing, time trials, or any form of spirited driving where the engine lives in the upper- RPM range then upgraded valve springs are a must.
The Manley Performance Valve Springs and Retainers are fabricated from high grade steel, and it is a complete set for both the intake and exhaust location. These springs can handle up to a 10k RPM rev when combined with Manley titanium retainers.