In 1953, Mr Bob Porter, of Boon & Porter Ltd., Riley Distributors, took his "RM" type 2.5 litre Riley to Montlhery, and covered just over 96 miles in an hour. His desire to do the "ton" resulted in him asking the Competition Committee of BMC if they would prepare a Riley Pathfinder for him. "And", he added, "to make the thing more difficult - and therefore more worthwhile - let’s run ‘six up’, with a car full of journalists!" Ken Wharton had already been doing some high-speed test work for BMC with the MGA. Quite independently of Porter, he had already suggested that he be allowed to take an MGA to Montlhery with the same end in view. John Thornley decided to take the idea a step further and opted for a mass-onslaught on this achievement.

At about the same time, BMC were feeling rather pleased with the behaviour and performance of the Class 3 (Modified Production Touring Car) Austin Westminster. Together with this, Ken Wharton had just had a splendid drive in such a car in the Production Car Races at Oulton Park. The idea was therefore not so far fetched for an attack on the "100-miles -in-the-hour" using BMC products, and the chance to do it with FIVE cars made the attempt even more challenging. On a more-the-merrier basis, the Austin-Healey stood ready-made for the job, and the Wolseley 6/90 was clearly a potential starter. Thus it was decided to prepare the five cars, and to make the runs as Officially Observed Trials in the middle of the Earls Court Motor Show period.

Technically, the preparation fell into three parts. First, in order to achieve 100mph, it was necessary to ensure that each engine produced sufficient power to overcome the total drag of the vehicle at 100mph. If the engine gave insufficient power in its standard form, then any or all of the modifications permitted under Class 3 of the International Regulations covering Modified Series Production Cars would be applied. Secondly, each vehicle had to be so geared that this peak power was reached at, as nearly as possible, 100mph. Thirdly, the cars had to be extremely reliable to run through the hour at such a speed.

It was a distinct advantage in running at a place like Montlhery where continuous speed is possible. It is a peculiarity of a high-speed car that it “winds itself up” the longer (within limits) it runs. The MGA was thought to be fast enough in standard trim, and tests at M.I.R.A. had proved this to be the case. The Austin-Healey, similarly, would do the job with plenty in hand. The other cars, however, had to be geared and tuned in their standard form with an eye on acceleration and/or fuel economy, and needed some changes to secure the desired end.

The Modifications

The Riley Pathfinder was almost suitable as it stood, but some margin was required, particularly in view of that intended load of journalists. High compression pistons, bringing the ratio to 8.6 and a 3.7 final drive ratio were considered sufficient, and tests at M.I.R.A. proved this to be so. Similarly with the Wolseley 6/90, an increase in compression ration to 8:1, an increase of valve spring pressure to raise the rev. range to 5,000, and again a 3.7 rear axle ratio sufficed. In the case of the Westminster, where the main design feature had been economy, it was necessary to fit the twin carburettor induction system as used on the Wolseley 6/90. Additionally, though tests showed that an increase in axle ratio was not essential, and 3.7 gears proved to be the correct solution.

John Thornley was always positive about performance, and the reliability of the cars was never in doubt. He had been involved with record-breaking attempts before and was well aware that an engine could run for 59 minutes of the hour and then fall apart. It was common for record-breaking cars to run behind a wind shield (otherwise known as "in the collar") to aid maximum efficiency. In this case the cars were either in standard trim or tuned slightly above their normal production specification. All of the cars would be run on "pump" fuel (BP Super) which was specially shipped from England due to the lack of confidence about the quality of French premium grade fuel. The RAC sealed and supervised the shipment to ensure there was no "tampering". It was also important to ensure that they would only be driven fast enough to maintain the 100 miles in an hour, and not flat out.

Off they went, and despite the awful weather, back they came with the record and a jubilant group of journalists. In the event, the only involuntary stop was caused by a burst tyre, not helped by one driver trying to find the shortest way around the circuit and running into some "rough stuff".

The tests had proved that it was then possible for cars to sustain speeds of 100mph. At the time, the motorway system was only just getting started (as featured in the May 1999 issue of Safety Fast! - see page 17) and so there was little opportunity to run a car at that speed in the UK. However, throughout Europe and North America, roads had been built with speed in mind and 100mph was not so much of a problem. Driving from Cologne to Frankfurt with your right foot flat on the floor, was accepted as standard, and the reliability of the cars at that speed was no longer a concern.

For those who didn’t manage to drive their cars at such, these tests inspired the owner with confidence in the knowledge of the still larger safety factor which applied to their own particular conditions of use. It also did a great deal to promote the BMC range.

One of the journalists asked why these cars (obviously not referring to the MGA or Austin-Healey) were not tuned and geared to these standards in normal production. The reply was, "It’s a matter of acceleration and fuel economy. Not everyone wants to do - or even to be able to do - 100mph, even though their car can be made to do it will without any doubt bring satisfaction. Vehicles must be produced to provide the greatest satisfaction to the greatest number in the class and market for which they are intended.

With the higher axle ratios, acceleration is impaired and to 99% of drivers, good acceleration is more important than a three-figure maximum. To fit the Austin Westminster with two carburettors would increase the cost and impair its quite remarkable fuel economy.

An increase in compression ratio should improve fuel economy but this is dependant on the quality of fuels found throughout the motoring world. Standard cars are tuned for optimum performance and economy, and in this, as in almost every other facet of automobile design, the optimum is a compromise between sharply conflicting requirements".

The Nuffield Motors’ report, written at the time, gives a more graphic account of the achievement - it appears page right. Below are the specific details about each car, and the ‘markers’ at which they were all measured. è "Despite gale-force gusts of wind and torrential rain which, at time, threatened to flood the track, a land-mark in motoring history was created at Montlhery when five British Motor Corporation production models each covered more than 100 miles in one hour’s continuous driving. These "for sale over the counter" cars, which accomplished such an exceptional, if not unique, feat were a Riley Pathfinder which covered 108.03 miles in the hour with three passengers in addition to the driver, Bob Porter; an Austin-Healey 100, driven by Ron Flockhart which clocked 104.32 miles in the hour; one of the new M.G. series MGA with Ken Wharton at the wheel, for which the timekeepers recorded 102.54 mph; the Austin Westminster Saloon driven by Chief Superintendent John Gott of the Hertfordshire Police, which lapped for an hour at 101.99 mph; and a Wolseley Six-Ninety, also driven by the Superintendent, travelled 101.2 miles in the 60 minutes.

To cap these epic achievements, Superintendent Gott also took out the MGA in racing trim and averaged 112.36 miles in the hour. About three-quarters of an hour after his start on this particular trial, the MGA blew a tyre and Mr Gott had to start all over again, so that in one morning he travelled nearly 400 miles at 100 mph in three different cars.

Ken Wharton said that conditions were the worst he had ever seen at Montlhery. "I do not think that I would have ever made the attempt in a car in which I had not supreme confidence", he said. Mr Wharton flew to the circuit to make the record attempt, returning to London the same night.

Driving the Pathfinder, Bob Porter, a car agent, and well-known trials driver, was accompanied by his wife, Mollie, his sister-in-law, Mrs Sue Porter, and Mr Ray Jeffs, a London insurance broker. The car ran so well that Bob suggested to Marcus Chambers, the BMC Competitions Manager, that he should be allowed to take them on his official bid, and this was agreed.

As the Automobile Club de France’s official timekeeper recorded each lap, it soon became evident that Bob Porter’s faith in the Riley Pathfinder was fully justified. Indeed, in the early stages he was flagged down on more than one occasion, but despite obeying these signals, the Pathfinder averaged 108.03 miles in the hour. Mrs Mollie Porter said afterwards, "It was really just like a family outing. We were dressed quite normally - no crash hats or anything - and throughout the hour talked quite naturally with each other in the intervals between checking our stop watches with the official signals". Ron Flockhart, who, like Ken Wharton in the MGA, drove with hood and windscreens in position, said afterwards, "Weather conditions had deteriorated so badly that it was difficult for me to see my time signals, but once I had established that I was gaining 2 - 3 seconds on each lap over my minimum time requirements, I kept the rev counter at between 4,200 - 4,500 rpm in overdrive just in case I missed a signal. The car ran beautifully throughout. There were no incidents, but at times the force of the wind cut the speed to about 100 mph, whilst my maximum speed under good conditions was between 110 - 112 mph".

Some idea of the appaling conditions under which many of the tests were carried out can be gauged from the fact that on more than one occasion the gusts of wind were sufficiently strong to whip the lap signals from the hands of the mechanic as he tried to indicate position and timing to a driver.

Marcus Chambers, describing the organisation of these high-speed reliability and stamina tests, said, "I was told to take cars representative of the Corporation’s production models - saloons as well as sports cars - and see if they could maintain a speed of 100mph or more in an hour’s continuous motoring. All vehicles were to be run on pump fuel and oil available to the British motorist. To ensure this, the petrol and oil were sealed by the RAC, who witnessed it being drawn from source. Equally, no oil or petrol could be put in the cars at Montlhery unless the Automobile Club de France official scrutineer was present. "The only modifications allowed on the vehicles were those under Groups III and IV under FIA regulations".