1000hp Sunbeam 'Slug'

The Sunbeam 1000 HP Mystery, or "The Slug", is a land speed record-breaking car built by the Sunbeam Car Company of Wolverhampton that was powered by two aircraft engines. It was the first car to travel at over 200 mph. The car's last run was a demonstration circuit at Brooklands, running at slow speed on only one engine.
The engines were a pair of Sunbeam Matabele 22.4 litre aircraft engines, previously used in a powerboat. Although best known as the "1000 HP" car, its actual power was closer to 900 hp. One engine was mounted ahead of the driver, one behind. The rear engine was started first by compressed air, then the front engine was started through a mechanical friction clutch. Once synchronised, they were locked together with a dog clutch for the record attempt.
The car was designed by Captain Jack Irving, having new features such as all-enveloping bodywork that assisted aerodynamics. The car also had specially-made tyres capable of withstanding 200 mph, although only rated for 3½ minutes at these speeds[1]. One more primitive feature was the final drive to the rear axle using a pair of chains. Only weeks before the record attempt, J. G. Parry-Thomas had been decapitated when a similar chain in his car Babs had broken at speed. Although the Sunbeam's chains were enclosed below an armoured steel housing, these covers had been designed from the beginning, they were not added after Parry-Thomas' accident.
The Sunbeam 1000 HP was the first non-American car to run on Daytona Beach for a land speed record attempt. On 29 March 1927 Henry Segrave drove the car to a new land speed record of 203.79 mph, the first car to reach a speed over 200 mph.

The 1,000hp. Sunbeam Car.

Segrave’s world land speed record of 1926 only survived for just over a month because on 27th April, 1926, Brooklands racer Parry Thomas took his 27litre Liberty aero-engine car called ‘Babs’ to Pendine, and broke Segrave’s record at 169.3m.p.h. and raised it the following day to 171.02m.p.h.

Segrave immediately asked Coatalen if Sunbeam could retrieve the record, possibly with a car capable of reaching over 200m.p.h.

At the time there were two 420b.hp. Matabele aero engines in store in the works that had been previously used in the successful motor boat "Maple Leaf IV".

Coatalen immediately sketched out a suitable car to use them and after acceptance by the board, Captain J.S. Irving was asked to produce a detailed design.

The 12 cylinder engines would be mounted in-line, one at the front and the other at the rear of the car, with the driver in the middle. Each could deliver 500b.hp. at 2,000 r.p.m. and would drive a central gearbox with bevel gearing to a transverse shaft and a final chain drive to the rear wheels. Special wheels and tyres were designed by the Dunlop Rubber Company and a host of British manufacturers supplied specialised parts. The streamlined aluminium body was developed after tests in the wind tunnel at Vickers.

The 12 cylinder engines would be mounted in-line, one at the front and the other at the rear of the car, with the driver in the middle. Each could deliver 500b.hp. at 2,000 r.p.m. and would drive a central gearbox with bevel gearing to a transverse shaft and a final chain drive to the rear wheels. Special wheels and tyres were designed by the Dunlop Rubber Company and a host of British manufacturers supplied specialised parts. The streamlined aluminium body was developed after tests in the wind tunnel at Vickers.

The car, known as the 1,000hp. Sunbeam was shown to the press on 21st February, 1927 and it received a lot of attention. It was decided that the best place for the attempt would be Daytona Beach in Florida where there is a stretch of flat sand, 9 miles long.

There were many significant problems to be overcome before the attempt could be made in America, and all of these were left to Segrave himself.

Segrave had to make agreements with the relevant American Authorities and also with the American Automobile Association. He was also responsible for all shipping costs and for the wages of the team of support mechanics. To cover his expenses he arranged as much sponsorship as possible from the many accessory companies whose parts were used in the car.

Just before the car’s departure for America, Segrave’s rival Malcolm Campbell took a new ‘Bluebird’ car to Pendine and broke Thomas’s record, achieving 174.883m.p.h.

The 1,000hp. Sunbeam left Southampton on board a Cunard Liner bound for New York on 2nd March. Segrave was supported by Kenelm Lee Guinness, Lord Rossmore, and Dunlop's Experimental Engineer, Norman Freeman.

During the trip Segrave received some worrying news. Parry Thomas had immediately returned to Pendine with ‘Babs’ after hearing about Campbell’s new record. Even though he was not well he continued with the record attempt, but things went badly wrong during the return run, when a chain snapped, and the car went out of control, instantly killing Thomas. As the Sunbeam car was also chain driven, the drive system would be carefully checked before any record attempt began.

On arrival in New York the customs officials demanded £16,000 import duty for the car and equipment. The car was sent by rail to Daytona, and Segrave and the support team sailed to Jacksonville on the Clyde Line "Mohawk". At Jacksonville the party was greeted by the town's Mayor and they were invited to an official luncheon before their road journey to Daytona.

At Daytona, Segrave decided to make three runs. The first was to get used to driving the car, as he had only previously driven it slowly around the works. The second run would be at a modest speed to see how the car performed, and the third run would be the record attempt itself. On the second run conditions were not perfect and it was decided to delay the record attempt for a week, during which time several modifications were made to the car.

The record attempt was made on Tuesday 29th March and at 9.30a.m. Segrave brought the car onto the sand for the press photographers and news reporters.

An estimated crowd of 15,000 people came to view the event.

He started at the southern end of the beach and travelled northwards during the first run, which went well.

At the end of the run the wheels were changed, although the tyres were hardly worn, and the car was rapidly made ready for its return run.

The wind was blowing at 18m.p.h. from the north east and so this aided the second run, which was faster than the first. Unfortunately the car overran the 9-mile course and the brakes seemed to be ineffective.

In order to stop, he drove the car into the shallow water at the edge of the sea, and returned to the timing box for the result. It was later found that the aluminium brake shoes had greatly overheated and melted. Segrave was presented with the marvellous news that he had beaten Campbell’s record by 28m.p.h. and was the first man to exceed 200m.p.h. He thought that the car could go faster, but after consultation with Guinness and Lord Rossmore he decided to let the 203.792m.p.h. record stand.

After the remarkable achievement the team returned to Southampton on the liner "Berengaria".

They arrived on 12th April and were greeted by the Mayor and Mayoress who invited them to a civic luncheon, the first of many celebrations that took place during the following fortnight.

The 1,000hp. Sunbeam was put on display at Selfridges store in London and several thousand people came along see the now famous car.

Sunbeam was now a household name thanks to Segrave, his team, and the highly skilled workforce at Moorfields. The 1,000hp. car still survives today and can be seen at the National Motor Museum, Beaulieu.

Source: Wolverhampton History & Heritage