268° cams for street, strip and track engines in the 350-600hp range. Great with E85 and similar ethanol blend fuels. Suits 48-58mm turbo. Still maintains good throttle response, improved mid-range power. Broader power band and improved throttle response when using MIVEC. For up to 8000rpm and 35psi boost Kelford Cams recommend valve spring KVS63-BTK.