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[edit] Concept
The Brabham BT55 was intended to make a big step forward in aerodynamic performance for the team. The team had had a generally uncompetitive season in 1985 with the BT54. Aerodynamic performance had become more and more important in Formula One motor racing since the late 1960s. In the early 1980s, Formula One design had been dominated by ground effect. Ground effect is an aerodynamic effect which sucked cars down onto the track at high speed, giving them increased grip and allowing them to go round corners faster. The effect was created by shaping the underside of the car. From the 1983 season onwards, the Fédération Internationale de l'Automobile mandated that cars must have flat undersides to eliminate ground effect and reduce cornering speeds. Brabham's first attempt to meet the new regulations, the BT52, had been very effective, winning the drivers' title for Nelson Piquet in 1983. The BT53 and BT54 which followed were developments of the same aerodynamic concept, but by 1985 the team had reached the limit of aerodynamic development of the design. Although flat bottoms reduced the proportion of downforce which came from the underbody aerodynamics, ground effect remained a crucial part of the cars design. The team's options were somewhat limited by their continued use of the production-based inline four BMW engine, which was tall and heavy, and aslo only allowed for exhasut blowing on one side of the car. Murray was unable to get a full blown underbody diffuser to work. Newer purpose-designed V6 racing engines from Honda, TAG and Renault were proving "well designed V6 engined cars demonstrated markedly superior aerodynamic grip". They were also rivalling the outright power of the BMW unit and with greater fuel efficiency. The 1985 car won only one race, and Murray decided that a radical approach was needed: "Without doing something, 1986 was looking bleak. At the time we built the BT54, we knew we couldn't find any more downforce..."
A conventional straight four engine, like the BMW Brabham was using, is tall relative to other engine configurations like 'vee' or 'boxer' where the cylinders are tilted away from the vertical. In order to create a large amount of downforce by other means, Murray came up with the concept of a 'lowline' car, with very low bodywork over a tilted over engine, which would allow a large supply of air to reach the rear wing undisturbed. A similar approach of laying down a tall engine to reduce cross sectional area was used in 1950s Championship Car roadsters by the American Kurtis-Kraft and Epperly racing car constructors and by Colin Chapman in the 1958 front-engined Formula One Lotus 16.[1][2] In order to achieve this, the driver was placed in a lying down position and BMW designed a special version of their four cylinder turbocharged engine with the tall engine block, normally positioned vertically in the car, tilted almost horizontally (18° from horizontal) to reduce the overall height of the unit. Drivers had been placed in the reclining position by Lotus in the early 1960s, but were sitting more upright again by the 1980s.
Creation of rear downforce is the limiting factor - downforce being more difficult to generate at the back of the car due to the turbulence caused by air having flowed over the car before it gets there. Downforce must be balanced between the front and the rear of the car in order to maintain the balanced of the car.
[edit] Brabham BT19
[edit] In popular culture (yeuch!)
Criterion: Is the pop culture ref about the car, or does it merely include the car?
Brabham's world championship victory, and hence the car with which is was achieved, has been celebrated in special issue stamps......
Appears in footage shot for the film Grand Prix (film) (Spa race)
[edit] Odds & Sods
Despite considerable notice having been given for the start of the 3 litre formula, most teams did not have suitable engines ready for the start of the season. Ferrari and BRM were the only teams with the capacity to build their own engines. Ferrari had existing 3 litre sportscar units (true?) and had an engine prepared for the start of the season. BRM undertook the development of an H-126 unit, which was not ready until later in the season. The others were reliant on outside suppliers. Cooper-Maserati (using a stretched version of a 10 year old design), McLaren with a reduced capacity version of a Ford Indycar engine....? The rest of the serious competitors used under capacity engines: BRM used 2 litre versions of the previous years engines. These were also used by Lotus, who also, along with others (Eagle....), used 2 litre versions of Climax's FMWV or 2.7 litre versions of the venerable 4 cylinder Climax FPF engine. (too long)
Fuel was stored in aluminium tanks, one either side of the cockpit.
In the mid-1960s aerodynamic design was largely aimed at reducing drag and improving stability. Jack Brabham had been alarmed by the tendency of the Lotus 24 he borrowed in 1962 to wander across the road at high speed, caused by lift reducing the contact between the front wheels and the track. Ron Tauranac's work in the MIRA wind tunnel had led him to an understanding of the need to avoid aerodynamic forces lifting the front of the car. Frontal lift reduced the force acting on the front wheels and
Jack Brabham had appeared to be on the verge of retirement from driving during 1964, missing (X) races, usually in favour of Denny Hulme, with Dan Gurney leading the team on the track. Gurney left Brabham to form his own Eagle team at the end of 1964. Brabham has since said that he was reinvigorated by the Repco project.
BRO was based in (?) at New Haw
[edit] Racing history
Of the multi-cylinder engines, only the Ferrari and Maserati V12s were ready to compete reliably at the start of the season. Until the new engines were ready, teams used a variety of existing, undersized and consequently underpowered engines from Climax and BRM.
