Hillman Imp - Imps in Motorsport

Imps in Motorsport

The engine proved flexible and very easy to tune. The overhead camshaft design meant that the head could be flowed and ported to allow the engine to run at high speeds. Useful improvements in power could be gained by replacing the standard silencer with one that impeded the exhaust gas flow less and with better carburettors. However, in adapting the design to suit modern mass production methods, Rootes had left the engine somewhat more fragile than its Coventry Climax parent.

The Imp enjoyed modest success in both club and international rallying. Rootes introduced a homologation special called the Rally Imp in 1964. The Rally Imp featured many modifications over the standard model, the most important of which was an engine enlarged to 998 cc. Notable successes for this model include the 1965 Tulip Rally in which the works Imps of Rosemary Smith and "Tiny" Lewis finished first and second overall.

Imps were also successful racing cars. The privateer team of George Bevan dominated the British Saloon Car Championship (later known as the British Touring Car Championship) in the early 1970s. Driven by Bill McGovern, the Bevan Sunbeam Imp won the championship in 1970, 1971 and 1972 with limited factory support.

In UK club racing the Imp variants became highly successful in the under 1000 cc Special Saloon category. Notable exponents of the Imp in racing include Ian Forrest, Harry Simpson, Ricky Gauld, John Homewood, Roger Nathan, Gerry Birrell, Ray Payne and Chris Barter. To this day Imps still comepte on historic rallies in the UK, with the Vokes' car often making onto the podium in the HRCR Clubmans Rally Championship.

The Imp was also successfully raced and rallied in other parts of the world, notably Asia where Drivers like Andrew Bryson and Pardaman Singh regularly won saloon car categories even till as late as the eighties.

998 cc Imp engines were also used in 3-wheeled racing sidecars in the 1970s and 1980s. Exhaust systems were naturally constructed on a one off basis, and often sporting the Twin Weber twin choke set up. A number of sidecar crews raced Imp-engined outfits at the Isle of Man TT races, best placement being Roy Hanks in eleventh place in the 1976 TT 1000cc Sidecar. Imp-engined outfits are still regularly championed in classic racing.

Andy Chesman, the 1972 World Hydroplane champion using an Imp engine. He bought Imp specialist Greetham Engineering, and designed a wedge head to increase the 998cc engine to 125 bhp with twin 40DCOE Webers. He also fitted a spacer on top of the wet block to accommodate longer piston liners, increasing capacity to 1220cc. At the BP-sponsored Lake Windermere records week in October 1972, he raised the R1 Class water speed record to 89 miles per hour (143 km/h). He was killed in 1998 in a power boat accident, still holding the record.