STI springs are stiffer than stock springs and lower the vehicle's ride height by about 10mm.The lower center of gravity can reduce body roll and result in improved handling.
Inverted strut and spring design with variable height adjustment. Includes a 4-position strutdampening adjustment on front and rear struts. Strut diameter is increased from 22mm to 39mm on 2.5RS and WRX (equal diameter on the STI model). Springs initially lower body approximately 10mm on 2.5RS and WRX, 20mm on STI model, and may be adjusted an additional 30mm.