The Lotus Mark IX (1955) was an

aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...

-bodied sports racing car manufactured by Lotus Engineering Ltd. About thirty of the Mark IX sports racing cars were made. It was closely related to the Lotus model Mark VIII (1954), of which only about seven cars were made. These cars were largely based on the innovative space frame of the

Lotus Mark VI The Lotus Mark VI is the first production car by Lotus Cars. It was introduced by Colin Chapman in 1952 after previously building multiple trials and road racing cars. The heart of the Mark VI is a space frame chassis. Rather than a complete ...

(1952). The highly aerodynamic bodies were designed by Frank Costin and constructed by Williams & Pritchard Limited. During this early era, of 1954–1955, Lotus Engineering was still a fledgling company, and cars were delivered in different states of completion on special orders. Similar to the Mark VIII, the Mark IX was available in various configurations and different engines, including the 1500 cc MG, 1500 cc Connaught and 2-litre Bristol were fitted. However, the Mark IX designation is most often powered by the 1100 cc

Coventry Climax Coventry Climax was a British forklift truck, fire pump, racing, and other specialty engine manufacturer. History Pre WW1 The company was started in 1903 as Lee Stroyer, but two years later, following the departure of Stroyer, it was relocat ...

engine. Apparently two models of Mark IX were offered – the "Club" and the "Le Mans", the latter of which had larger drum brakes fitted. LotusIX-JBoxtrom-LimeRock2015

The chassis of the Mark IX was a new design, compared to that of the Mark VIII. Both were

space frame In architecture and structural engineering, a space frame or space structure ( 3D truss) is a rigid, lightweight, truss-like structure constructed from interlocking struts in a geometric pattern. Space frames can be used to span large areas with ...

s of brazed steel tube. The new chassis was an advance over the Mark VIII in terms of the efficiency of its design and avoiding the VIII's need for diaphragm-stiffening panels. However, both chassis still used an oversized lower rail of tube, a hang-over from the original design of the first Mark VI space frame. Compared to the Mark VIII, the Mark IX was shortened somewhat to a wheelbase of , and the body itself was about shorter than that of the Mark VIII. A total of about thirty of the Mark IX sports racing cars were produced in various forms, and these were successfully raced in both Europe and the US. The first two examples of the Mark IX were apparently delivered to the US with the 1100 cc Coventry Climax engine to compete in the 1955 running of the

12 Hours of Sebring The 12 Hours of Sebring is an annual motorsport endurance race for sports cars held at Sebring International Raceway, on the site of the former Hendricks Army Airfield World War II air base in Sebring, Florida, US. The event is the second round ...

race and were beaten by a

Porsche Spyder The Porsche 550 is a racing sports car produced by Porsche from 1953 until 1956. In that time only 90 Porsche 550s were produced, and they quickly established dominance in the 1.1- and 1.5- liter classes. The Porsche 550 is a mid-engine car with ...

. These cars were actually entered as Lotus Mark VIII models in the G class by Frank Miller of Larchmont, NY and by Bobby Burns and Norman J. Scott of Houston TX in, respectively, car numbers 78 and 79. The Lotus Works Team entered at least one Mark IX in the

Le Mans 24 hour The 24 Hours of Le Mans (french: link=no, 24 Heures du Mans) is an endurance-focused sports car race held annually near the town of Le Mans, France. It is the world's oldest active endurance racing event. Unlike fixed-distance races whose w ...

race in 1955, driven by Chapman, which may have been equipped with

disc brakes A disc brake is a type of brake that uses the calipers to squeeze pairs of pads against a disc or a "rotor" to create friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hol ...

. However, the car was disqualified apparently due to his reversing the car to re-enter the race track after going off course.

References

{{DEFAULTSORT:Lotus Mark Ix Mark 09