Theodore Racing was formed in 1974 by Teddy Yip to run cars for the Formula 5000 season. Soon after one of the F5000 car owners Sid Taylor joined Yip as a partner he helped fuel the teams ambition to venture into Formula One.
In 1974 Theodore began by independently running their own Ensign Formula One car (between the years of 1974 - 77) before becoming a constructor in 1978, the first car to be manufactured was the Theodore TR1.
An existing design was bought from Ralt constructor Ron Tauranac and the first car was built up at Theodore's new base, Ralt’s former workshop in Woking. The car followed the lines of Formula Two Ralt RT1, but bulked up for Formula One, it was highly conventional, to the point of being old fashioned, in comparison with larger constructor teams such as Williams' with their new FW06.
Eddie Cheever was picked to drive the Theodore at the opening races of 1978, but failed to qualify for either. He fled to the Hesketh team, and was replaced by Keke Rosberg, who immediately wrecked the first car while testing in South Africa. With the second, improved, TR1 he qualified comfortably for the South African GP, and then scored an amazing win in soaking wet conditions at the non-championship Silverstone International Trophy, where almost everyone else skated off the track. Thereafter the Theodore team had a demoralising time, failing to even pre-qualify at the Long Beach GP or at Monaco. After two more races where Rosberg looked no closer to getting on the grid, the TR1 was dropped and Yip.
Currently the Theodore TR1 is owned by Phil Hall.