Raby was a garage owner from Brighton, who began racing with a homemade special, which he christened 'Puddle Jumper', in the early fifties in 500cc Formula 3. However he became really competitive when he switched to a Cooper in 1956. He then switched to sportscar racing with Cooper and Elva cars, sharing a Cooper with Jack Brabham in the 1957 Le Mans 24 Hours.
He returned to single-seaters in 1959 with both a Cooper and a Hume-Climax, gaining success Formula Libre races. Before entering the highly competetive world of Formula Junior in 1961-62. He then bought the ex-Keith Greene Gilby-BRM and competed in F1 races in 1963. He came third at Vallelunga in the Rome GP, but precious little else, and in 1964-65 he switched to a Brabham BT3, still without success.
In 1966, with the introduction of the 3 litre formula, Raby entered F2 with a Brabham BT14-Cosworth. He came fourth at the Eifelrennen before his season ended with a big crash at Brands Hatch.
Despite his age, Ian undertook a full season of Formula 2 with a Lotus-engined Brabham in 1967, gaining the occasional top-six finish. Then at the end of July a serious crash at Zandvoort left him hospitalised with multiple injuries to which, he succumbed at the start of November.