It was considered by BMC management to use the 1800's in preference to the much smaller (but rally proven) Mini 850's.
Of the twelve cars entered, four were BMC works cars and were driven by top line rally, racing and endurance drivers from the UK, Australia and Ireland.
A reconnaissance (recce) survey of the route by some drivers, decided a three man crew would be needed for safety reasons instead of two crew as was previously suggested.
All BMC works cars were Morris/Austin 1800's prepared at the Competitions Department at the BMC factory in Abingdon, near Oxford U.K. and fitted out with full rally equipment. Also certain modifications were made to lighten the weight and increase power. There were other modifications made that would make life easier for the drivers and crew of each car.
Car 51, is a BMC works entered 1800 that finished in second place. This car was crewed by Paddy Hopkirk (Ireland), Tony Nash (UK) and Alex Poole (Ireland). The car was built and prepared by Gerald Wiffen, who treated it as if it were his baby.
Gerald and his colleagues contributed a significant amount to the success of this car in the Marathon, according to Hopkirk. Gerald also went along with the BMC service crew on the Marathon to provide the much needed servicing and mechanical support.
Tony Nash performed a recce from London to Bombay and Paddy flew to Australia and recce' d part of the Australian section. These notes were incorporated into the recce notes the BMC works drivers used.
Not much was changed to the 'B' Series engine. The cars had flat top pistons and used the Mk I 1800 heads. The camshaft was the standard MGB unit and engine was bored out + 40 thou " to increase capacity to 1,845 cc from the standard 1800cc. The inlet manifold was ported and polished and twin HS 6 SU 1 3/4 " carburettors were fitted. Apart from that it remained pretty much the same engine and transmission that were fitted to all BMC 1800's.
The four BMC Teams consisted of three crew members per car. This was decided because of the long distance of the Marathon and also because the cars were built like tanks in the first place.
A year earlier the popular American Consumer Advocate, Ralph Nader, said that the Austin 1800 was among the safest cars built. He said because of the way the engine was situated, and the design of the bulkhead (that houses the front displacers), in the event of a head on accident, the engine would be pushed back and under the bulkhead, away from the driver and passengers.
Service teams were provided for the BMC vehicles all along the route (as were service teams provided for many of the other different teams cars).
Dunlop SP 44's were the choice of tyres. It was a new type of radial tyre with reinforced sidewall rubber strips. These tyres were also used by many other drivers.
It needs to be mentioned here that all BMC works cars finished the Marathon and in quite respectable placings. Car 51, as mentioned earlier finished in second place, car 61, finished in fifth place, car 31, finished in twenty-first place and car 4 finished in twenty-third place. A complete list of drivers and BMC cars is listed in the BMC 1800 Team page.
There were eight other BMC 1800 entries - not part of the Official BMC works team however some of them were given some modifications the works team cars had.
Only two cars did not finish due to mechanical failure and a third had to retire because a crew member (White) was injured when he fell down a servicing pit causing him to be taken to hospital with kidney damage and other injuries.
The rules were clear: All crew members who started the Marathon, must also finish.
Car 64, ORX 663F was a works car built by Brian Moylan and crewed by J.T. Kingsley/Evan Cook Ltd. Flt.Lts. T. Kingsley, D.A. Bell and P.R. Evans. Finished 19th
The non-works (BMC Competitions Department prepared) BMC 1800 cars were:
Car 71, NKG 777G. Vantona Everwear. B.L. Field, R.D. Tilley and D. Jones. Finished 28th.
Car 17, VLM 128G. Royal Navy. Capts. Hans Hamilton, I.J. Lees-Spalding and P.W.S. Stearns. Finished 31st.
Car 70, VLT 1G. Wilsons Motor Caravan Centre. A.H. Wilson, F. McDonnell and C. Taylor. Finished 34th.
Car 77, MTB 150G. Big 'N' Cash-Carry Group. R. Eaves, J. Vipond and F. Bainbridge. Finished 35th.
Car 65, ARA 65G. Hydraulic Machinery (GB) Ltd. G.D. White, J.J. Jeffcoat and D.H. Dunnell. DNF (retired) - White was injured.
Car 16, NAM 616G. D.A. Corbett, G.J. Mabbs and T. Fisk. DNF (con-rod through the crankcase - in Yugoslavia).
Car 21, UDM 999G. Hillcrest Motor Co. B.G. Williams, M.E. Thomas and B. Hughes. DNF (missing after Teheran).
All in all, a very creditable performance by a car that had relatively few modifications and was considered too under-powered and not suitable for such a rally.
In hindsight, the popular Mini 850 would have also been a worthy contender, c'est la vie.