Leyland Comet

The semi-bonneted original Comet was first shown in December 1947.^[1] While intended mainly for export, it was also sold in the home market. The wheelbase is 17.5 ft (5.3 m) and the gross weight 8.75 long tons (8,890 kg).^[2] A coach model seating 33, sharing the same front design, appeared in 1948.^[1] The cab was built by Briggs Motor Bodies and was shared with the Ford Thames ET6 and Dodge 100.^[3] Ford purchased Briggs in 1953, meaning Leyland (and Dodge) were forced to develop new cabs. The original engines were a 75 hp (56 kW) diesel or a 100 hp (75 kW) petrol unit; the petrol version was rarely seen in Britain.^[4]

In 1950 the diesel engine was updated to the new 5.76 litre Leyland O.350 unit, now with 90 hp (67 kW). Maximum weight was increased to 12 long tons (12,200 kg); models for tropical zones received a considerably lower rating.^[5] In 1955 the maximum power output was increased again, to 100 hp (75 kW) at 2200 rpm, as the new O.350 Mk. III engine replaced the previous version.^[5]

In 1952 a cab over version of the Comet became available. This was sold next to the bonneted model until 1955/56, depending on the market. Power from the Leyland O.350 engine in the bonneted version went from 90 to 100 hp (67 to 75 kW) in 1955. This model continued in production until 1958, although Australian models continued to use this cab into the early 1960s. This model also entered production in India after having received government approval in 1951.^[6] Ashok Motors, Ashok Leyland after 1954, manufactured it locally. The original front clip design remained in use into the early 1970s. Ashok Leyland proceeded to develop a simplified local cab design and continued to build the Comet into the 1990s.

In 1958, as part of an effectivization program, the Comet received a new cab – called the "Vista Vue" cab, it was developed by Albion for a variety of their models. Dodge UK also used it for their 300 model, consequently this cabin shape is often referred to as the "LAD" design. There was also a heavier duty "Super Comet" model introduced, which eventually largely supplanted the "regular" Comet. Also in 1958 the 375 engine, based on the preceding design and rated at 110 hp, became available in the "Vista Vue" cab. Following this, a redesigned engine with cross-flow cylinder head was released. Initially it was a 370 (6.1 litre) at 110 hp, followed by a 400 (6.6 litre) option at 125 hp.