After studying business administration Akagi joined his father's company Kenzai in 1966. The firm was involved in property development and after taking control Akagi built it up with great success until 1981 when it became part of Marusho Kosan Ltd., a real estate sales, leasing and management company. This in turn became part of the Leyton House Group which he established in 1984, involving 21 companies involved in real estate, restaurants, travel, sports and clothing shops.In order to promote the Leyton House brand Akagi decided to become a motor racing sponsor. His first contact with the sport was in support of rising Japanese star Akira Hagiwara. Unfortunately Hagiwara was killed in April 1986 in an accident in a Mercedes 190E touring car at the Sugo racing circuit.That same year Akagi decided on an international sponsorship program and funded Ivan Capelli's Genoa Racing March in the International Formula 3000 Championship. Capelli won the European title and in 1987 graduated to F1 with the revived March F1 team. Leyton House became March's primary sponsor. At the same time Akagi sponsored a successful Japanese Formula 3000 team, winning the 1987 title with Kazuyoshi Hoshino. In 1988 he acquired a shareholding in March and the following year he traded those shares and paid another $6m in order to buy all March's racing operations, including the F1 team, the company's windtunnel and all March's Formula 3000 operations. The entire operation was renamed Leyton House Racing.In the autumn of 1991 Akagi ran into trouble with the Japanese authorities in connection with the massive Fuji Bank scandal involving illegal loans to businessmen. Akagi sold the F1 team to a consortium led by Ken Marrable, one of his British associates. The team struggled on into 1993 but was then closed down.