Thisquick ratio power steering gear box is a great upgradeto replace the Saginaw/Delphi 800 series found in most 1965 and up GM muscle cars. This all new power steering box has a quick 12.7:1 ratio with firm modern steering feel. Bolts directly to the stock location and works with the factory power steering pitman arm. When using ina power steering conversion, a new power steering pitman arm will be required.