though this was added a few years after its introduction. One problem with the Range Rover chassis was that it suffered considerably from body roll. Because of this, the suspension was lowered by in 1980, and later gained anti-roll bars. Air suspension was introduced in late 1992 for high-end 1993 models. Most Range Rovers had a wheelbase. However, 1992 saw the introduction of a more luxurious model, branded the LSE in the United Kingdom and County LWB (long wheelbase) in the United States, providing expansive rear-passenger legroom absent from the 100-inch wheelbase models. These had a wheelbase, air suspension and 4.2-litre engines. The 100-inch Range Rover chassis became the basis for the Land Rover Discovery, introduced in 1989. Engines Originally, the Range Rover was fitted with a detuned version of the Buick-derived Rover V8 engine. The engine was increased to a displacement of for the 1989 model year, and in 1992. Petrol-fuelled Range Rovers were fitted with carburettors until 1986, when they were replaced by Lucas electronic fuel injection, improving both performance and fuel economy. The Lucas injection system continued to evolve over the next several years, culminating in the 1990 to 1995 Lucas 14CUX. Some export markets retained carburettors, with the original Zenith/Stromberg manufactured units being replaced by Skinners Union (SU)-manufactured items. From 1979 onwards, Land Rover collaborated with Perkins on Project Iceberg, an effort to develop a diesel version of the Range Rover's 3.5-litre V8 engine. Both naturally aspirated and turbocharged versions were built, but the all-alloy engine blocks failed under the much greater pressures involved in diesel operation. The project was, therefore, abandoned. The effort to strengthen the Rover V8 for diesel operation was not, however, completely wasted; the 4.2-litre petrol variant of the engine used crankshaft castings developed in the Iceberg project. Because of the Iceberg failure, it was not until 1986 that Range Rovers gained diesel engines from the factory. The more efficient inline-four VM Motori diesel from Italy was made available as an option for the heavily taxed European market as the 'Turbo D' model, and were increased to in 1989. The VM engines were highly advanced and refined diesel engines for their time but were received poorly by the UK press due to their inconsistent torque delivery compared to the V8 models. To counter these criticisms Land Rover used a Turbo D Range Rover to set several speed and endurance records for diesel