260° solid lifter cams to suit 32-40mm restrictor plate and GPA rally 4G63 engines. Good throttle response. 48-58mm turbo. Broader power band and improved throttle response when using MIVEC. Not for OEM hydraulic lifters, must convert to solid lifter. For up to 8000rpm and 35psi boost Kelford Cams recommend valve spring KVS63-BTK.