R.T. Quaife Engineering, Ltd. is a British manufacturer of automotive drivetrain products. It designs and manufactures motorsport and performance orientated gearboxes, gearkits, differentials, steering racks and axle kits, along with many other associated drivetrain products. The company was founded in 1965, by Rod Quaife and is now run and owned by Sharon Quaife-Hobbs, Sharon's son Adrian Quaife-Hobbs is the owner of Pro-Sim and is a professional racing driver. The early days at Quaife were spent manufacturing performance motorcycle gearkits, most notably close ratio 5-speed units for Triumph, BSA and Norton. Quaife also took on subcontracted work from AMC; the makers of Matchless and AJS motorcycles. Quaife gearkits were used to achieve victories in the Daytona Speedway and Isle of Man TT. Based near Sevenoaks, Kent they have two sites, one in Sevenoaks and the other, their OEM production facility, in Gillingham. Quaife's signature product is its line of automatic torque biasing differentials, a form of limited slip differential that employ helical gears rather than clutch mechanisms that are controlled mechanically. These differentials are usually available as aftermarket items, but for some models are specified by automobile manufacturers as OEM equipment. Quaife's ATB differential is now available in over 300 different applications, covering everything from Alfa Romeo to Volvo. Originally developed in the 1980s, the ATB differential appeals to many performance and racing car enthusiasts for its mix of traction-enhancing abilities, reliability, smooth operation and its 'fit and forget' installation. Within many markets, the Quaife ATB differential also comes with a lifetime warranty; applicable to both road and race environments. Aside from manufacturing precision engineered differentials, Quaife also produces highly sought after sequential gearboxes. The Quaife QBE60G and QBE69G heavy duty 6-speed sequential gearboxes are offered with several bell housings to fit a number of popular racing applications. Other sequential transmissions cater for applications including the Ford GT40, Land Rover V8, Mitsubishi EVO 4–9, Nissan Skyline GTR R32-R34 and Porsche 996 and 997. Quaife also offers many transmissions in synchromesh and dog engagement formats. Quaife's range of motorsport gearkits replace the standard internals of many popular transmissions found in both classic and contemporary vehicles. Initially the company focused on classic British cars as well as those manufactured by Ford Motor Company. Over recent years, the company has expanded its gearkit offering by catering for many front-wheel drive vehicles including Honda K-Series, Volkswagen 02M/02Q and a number of Ford applications. Elsewhere, Quaife