Engine Code: 4AG(Z)E
Fits: 1985-1991 Toyota Corolla GTS
HKS valve springs are stiffer springs specifically designed for use with HKS camshafts. As valve train dynamics change with the use of high performance cam profiles and greater lift, stiffer valve springs are needed to optimize valve movement. When changing to a high lift cam, stock springs cannot match the increased valve train movement. Therefore HKS engineered valve springs that are precisely matched to the characteristics of HKS camshafts.