BRABHAM / MOTOR RACING DEVELOPMENT (MRD) CARS

List of Brabham / MRD cars produced from 1961 to 1974

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Brabham BT1 – Produced 1961 – 1 made
Formula Junior car originally know as Motor Racing Development (MRD) but retrospectively renamed as first Brabham in the BT series. Spaceframe car with aluminium body, Ford engine, modified VW gearbox, drum brakes inboard at rear. Front suspension by coil springs, lower wishbone, single upper arms and Y-shaped radius rods. Rear suspension by coil springs, board-based upper wishbone, lower links and twin radius rods. Car bought and successfully raced by Gavin Youl, winning the Australian National Formula Junior Championship in March 1962.

Brabham BT2 – Produced 1962 – 11 made
Development of the BT1 Formula Junior car but with Hewland Mk 5 gearbox and glassfibre body by Specialised Mouldings. Girling desc brakes all round and rear brakes now mounted outboard for easier maintenance and to avoid possible problems with oil on discs.

Brabham BT3 – Produced 1962 – 1 made
Formula One car built along similar lines to BT2 but with Coventry Climax FPF 1.5 litre V8 engine, 6-speed Colotti gearbox, later changed to 5-speed Hewland before car was sold to Ian Raby. Rear suspension featured parallel transverse lower links. Initially ran with Lola rear wheels, later changed to Brabham wheels.

Brabham BT4 – Produced 1962 – 3 made
‘International’ car powered by Coventry Climax FPF engine, mainly used in Australasian Tasman series run to 2.5 litre Formula One rules until 1970. Different engine bay from BT3. Jack Brabham won the 1963 Australian GP and Graham Hill 1964 Tasman race at Longford driving BT4-Climax.

Brabham BT5 – Produced 1963 – 2 made
Sports-racing car powered by a 1.6 litre Lotus-Ford Twin Cam engine and shared many components with BT6 Formula Junior cars. One car sold to Ian Walker for Frank Gardner and Paul Hawkins to drive.

Brabham BT6 – Produced 1963 – 20 made
Further development of BT2 Formula Junior car, some examples adapted to Formula 2 and Formula 3 specification in 1964. Italian firm De Sanctis built copies of BT6 in 1964.

Brabham BT7 – Produced 1963 – 2 made
Development of BT3 with longer wheelbase, Hewland gearbox, revised bodywork and rear suspension by upper wishbones and lower transverse links.

Brabham BT7A – Produced 1963 – 3 made
Similar to BT7 but fitted with 2.5 litre Coventry Climax FPF engine. Jack Brabham won 1964 Australian GP with a BT7A-Climax.

Brabham BT8 – (None made)
Car designed but not built in this form. Wheel and tyres sizes changed leading to redesign as BT8A.

Brabham BT8A – Produced 1964-6 – made 12 made
Sports-racing car produced to use a batch of 2.0, 2.5 and 2.7 litre Coventry Climax engined after prototype initially raced with 2 litre BRM V8 engine. Roger Nathan adapted his BT8A to take 3.5 litre Oldsmobile V8, but experiment was unsuccessful. Many components common with BT11 F1 car.

Brabham BT9 – Produced 1964 – 13 made
Further development of BT9 Formula Junior car with Jack Knight gearbox derived from Hillman Imp transmission. Silvio Moser used BT9 to win four international races.

Brabham BT10 – Produced 1964 – 17 made
Formula 2 development of BT6 single-seater, usually with Cosworth SCA engine and Hewland gearbox. Steel sheeting welded to bottom chassis tubes for added stiffness and to achieve minimum weight requirement. Pendant pedals in place of floor mounted pedals of FJ/F3 cars, a distinction which continued 1968 and the BT23 series. BT10 won nine of 18 F2 races in 1964. Some cars raced inItaly powered by dohc engine based on Fiat block. French firm Alpine bought cars, kits and the right to manufacture BT10’s.

Brabham BT11 – Produced 1964 – 5 made
A revised version of the BT10 built around the smaller and wider 13in tyres introduced by Dunlop.

Brabham BT11A – Produced 1965 – 5 made
A version of the previous car usually fitted with a Coventry Climax FPF engine. Certain BT11A chassis components supplied to LDS special manufacturer Doug Serrurier for use in South African Gold Star Championship races by Sam Tingle. The last of Serruruer’s line of LDS models came in 1965-6 with two cars based on the Brabham BT16.

Brabham BT12 – Produced 1964 – 1 made
IndyCar commissioned by John Zink and entered as John Zink Truck Burner Special with 4.2 litre Offenhauser engine and Hewland GD300 gearbox. Retired atIndianapolis in 1964 but subsequently won four Championship races in hands of Jim McElreath (once with Ford V8 engine). Clint Brawner was permitted to copy BT12, his version being called a Hawk, though entered as the Dean Van Lines Special. Mario Andretti won the 1965 IndyCar Championship with this car which was then further developed and although still essentially a Brabham, was commonlt referred to as the Brawner of the Brawner-Hawk.

Brabham BT13 – (None made)
Number not allocated. Ron was certainly nor superstitious about 13 as this the date of his birthday, so he thinks it was because Jack Brabham was against it.

Brabham BT14 – Produced 1965-6 – 10 made
Formule libre single-seater used for this class of racing at club level as well as for hillclimbing. Form the BT14 would emerge the design of a Formula A / Formula 5000 car in the late 1960’s.

Brabham BT15 – Produced 1965-6 – 58 made
Formula 3 car shared the shame chassis with the BT14 and BT16, but fitted with Girling brakes and Hewland Mk6 gearbox. Nearly all cars fitted with Cosworth Ford MAE engines. A very successful car winning 42 major races.

Brabham BT16 – Produced 1965 – 12 made
Formula 2 car, mainly powered by Cosworth SCA engine although some cars used BRM inits. Jack Brabham ran a BT16 with Honda dohc engine in three late season races in 1965 using them for the works team in 1966.

Brabham BT16A – Produced 1965 – 21 made
Formula 3 car built largely to Formula 2 chassis specification.

Brabham BT17 – Produced 1966 – 1 made
Prototype Group 7 sports-racing car, basically a stretched BT8A with wider wheels (front 13x8in, rear 13x10in) and bigger brakes etc. Originally fitted with a 4.3 litre Repco engine, then by a 3 litre version. Car later sold to private owner.

Brabham BT18 – Produced 1966 – 1 made
Formula 2 car with a 2.5in longer engine bay for improved accessibility and longer unrights to copy with greater stresses generated by even wider tyres. Customer cars powered by Cosworth SCA engines but works team ran dohc Honda engines and had rubber doughnuts attached to the drive-shafts.Brabham BT18A – Produced 1966 – 32 made
Formula 3 version of the previous carBrabham BT18B – Produced 1966 – 8 made
Car built to special order for the Honda racing school with a tuned FordKent engine. Essentially a Formula Ford 1600 car produced some 18 months before this formula was officially launched.

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Brabham BT19 – Produced 1966 – 1 made
One-off car originally designed for the stillborn Conventry Climax 1.5-litre flat-16 engine in 1965, then converted to run with 3-litre Repco RB620 V8 engine and Hewland DG300 gearbox. Wheel sizes 15x8in front, 15x10in rear.
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Brabham BT20 – Produced 1966 – 2 made
Improved BT19 with longer wheelbase and stiffer frame, but still with RB620 engine and DG300 gearbox.

Brabham BT21 – Produced 1966-8 – 50 made

Further Formula Three development of BT18 single-seater with Hewland H6 gearbox and virtually all cars fitted with Ford-based engines. Shallower spaceframe than previous cars and detail revisions to suspension, including wider track, and slimmer body. Arrived in late 1966 but destined to become most popular with Brabham model.

Brabham BT21A – Produced 1967 – 10 made
Formule Libre car with Lotus-Ford Twin Cam engine.

Brabham BT21B – Produced 1967-8 – 31 made
Update of BT21 with 13x7in front and 13x9in rear wheels and Hewland FT200 gearbox. Birel built by Ernesto and Vittorio Brambilla was a BT21 copy.

Brabham BT21C – Produced 1967-8 – 18 made
Formule Libre version of previous car.

Brabham BT21X – Produced 1968 – 1 made
Works development Formula Three car with stiffer spaceframe based on BT23

Brabham BT22 – Produced 1966 – 1 made
Formule Libre car with 2.5-litre Conventry Climax FPF engine, originally built for a Scottish customer but later sold to New Zealand driver Jim Palmer for Tasman series races. Car based on BT11A but with BT19 suspension geometry.

Brabham BT23 – Produced 1967 – 9 made
Formula Two car with spaceframe stiffened by stress-bearing panels and engine bay reinforced with additional small tubes. Fitted with Brabham-made uprights and stub-axles.

Brabham BT23A – Produced 1967 – 1 made
International version powered by 2.5-litre Repco engine and used by Jack Brabham for 1967 Tasman series, winner at Longford.

Brabham BT23B – Produced 1967 – 3 made
Hillclimb version of BT23 powered by Conventry Climax FPF engine.

Brabham BT23C – Produced 1967-8 – 13 made
Formula Two version powered by 1.6-litre Cosworth FVA engine driving through Hewland FT200 gearbox.

Brabham BT23D – Produced 1967 – 1 made
Tasman car powered by Alfa Romeo Tipo 33 engine built for Kevin Bartlett, who won 1968 Australian Gold Star Championship with it.

Brabham BT23E – Produced 1967 – 1 made
Tasman car with Repco V8 engine.

Brabham BT23F – Produced 1968 – 1 made
Car built for SCCA Formula B (Atlantic) racing with Lotus-Ford Twin Cam engine and Hewland FT200 gearbox.

Brabham BT23G – Produced 1968 – 2 made
Similar to BT23F but with Hewland Mk 5 gearbox.

Brabham BT24 – Produced 1967-8 – 3 made
Formula One car following design of BT23A Tasman chassis apart from wider engine bay. More powerful Repco V8 engine, designated 740 and producing 330bhp, driving through Hewland DG300 transmission. BT24 almost as compact as current F2 car.

Brabham BT25 – Produced 1968 – 2 made
Indianapolis car – first Brabham to feature tubular chassis reinforced with stressed aluminium panels to meet requirement of bag-type fuel tanks. Fitted with 4.2-litre Repco V8 engine and Hewland LG500 gearbox. Wheels 15×8.5in front, 15×9.5in rear.

Brabham BT26 – Produced 1968 – 3 made
Further development of BT24 Formula One car, longer and with wider track. Fitted with dohc four-valve Repco RB860 engine. Wheels 15x11in front, 15x14in rear.

Brabham BT27 – None made
Type number reserved for 4WD Formula One car which did not progress beyond design study.

Brabham BT28 – Produced 1969-70 – 42 made
Formula Three car based on BT21X with stiffer frame and new bodywork.Tyre widths increased to 9in front, 12in rear.

Brabham BT29 – Produced 1969-70 – 29 made
Formula B car, closer in specification to Formula Two than Formula Three.Tyre widths 10in front, 14in rear. One or two cars subsequently uprated to run in Formula Two.

Brabham BT30 – Produced 1969-70 – 26 made
Formula Two car with more complicated spaceframe than Formula Three sibling. Wings appeared in Formula Two in 1969. Bag tanks housed in distinctive bodyside bulges.

Brabham BT30X – Produced 1969 – 2 made
Hillclimb car developed from BT30 with 1.8-litre Cosworth FVA engine, stronger drive-shafts, smaller breaks and tiny fuel tanks.

Brabham BT31 – Produced 1969 – 1 made
International car fitted with Conventry Climax 2-litre V8 engine and used in Tasman series.

Brabham BT32 – Produced 1970 – 1 made
Indianapolis car with turbocharged 2.6-litre Offenhauser engine, Weisman gearbox and 15x10in front and 15x14in rear wheels.

Brabham BT33 – Produced 1970 – 4 made
First monocoque Brabham Formula One car. Cosworth Ford DFV engine driving through Hewland DG300 gearbox. Wheels 13x11in front, 13x16in rear.

Brabham BT34 – Produced 1971 – 1 made
Formula One car nicknamed the ‘lobster claw’ because of its twin water radiator nacelles ahead of the front wheels, with adjustable aerofoil section linking them. Built for Graham Hill with slab-sided monocoque and outboard suspension and front brakes. Front track of 62in, 4in wider than BT33.

Brabham BT35A – Produced 1971 – 3 made
SCCA Formula Atlantic version of multi-formula car with inboard rear brakes, Ford 1600 Twin Cam engine and Hewland FT200 gearbox.

Brabham BT35B – Produced 1971 – 7 made
Formula B/Atlantic car with 13x10in front and 13x14in rear tyres, outboard rear brakes and Hewland FT200 gearbox.

Brabham BT35C – Produced 1971 – 27 made
Formula Three version with 13x9in front and 13x10in rear tyres and Hewland Mk 8 gearbox.

Brabham BT35X – Produced 1971 – 4 made
Hillclimb car with heavy-duty drive-shafts. Two cars fitted with 1.6-litre Cosworth Ford Twin Cam engine and one with 1.8-litre Cosworth FVC engine, all with Hewland FT200 gearbox and Formula Atlantic-size wheels. One car with 5-litre Repco V8 engine, Hewland DG300 gearbox and 16in wide rear wheels, used by Mike MacDowell to win RAC Hillclimb Championship.

Brabham BT36 – Produced 1971 – 9 made
Formula Two car similar to BT35B but with Cosworth FVA engine.

Brabham BT36X – Produced 1972 – 1 made
Hillclimb car with 5-litre Repco V8 engine, Hewland DG300 gearbox and 16in wide rear wheels.

BT37 – Produced 1972 – 2 made
Revision of Ron Tauranac’s BT33 by Ralph Bellamy with conventional front radiator and slightly narrower front and rear tracks.

Brabham BT38 – Produced 1972 – 16 made
Formula Two car, designed largely by Geoff Ferris but with suspension similar to BT36. First customer Brabham with monocoque chassis. Chisel nose, side radiators and tubular frame behind cockpit.

Brabham BT38B – Produced 1972 – 5 made
Formula B version of BT38

Brabham BT38C – Produced 1972 – 1 made
Formula Three version of BT38

Brabham BT39 – Produced 1972 – 1 made
Formula One car based on BT38 chassis but fitted with Weslake V12 engine and Hewland FG400 gearbox. Tested but not raced.

Brabham BT40 – Produced 1973 – 28 made
Formula Two (9 built) and Formula B (19 built) car.

Brabham BT41 – Produced 1973 – 21 made
Formula Three car

Brabham BT43 – Produced 1973-4 – 1 made
Formula 5000 car.

With thanks to Mike Lawrence, the author of Brabham+Ralt+Honda, for the information provided above.