These 274ø/276ø Stage 2 racing cams are specifically designed for turbocharged 2GR engines, and will work with a single 68mm+ turbo or twin turbo setups with 54-62mm range. These cams are best suited for engines making 700-1000hp and are compatible with VVT-i. They work particularly well with E85 fuel. We recommend upgrading the valve spring and retainer to KVS263 for engines revving up to 8000rpm and 30psi boost.