Pete05
Premium
- 7,173
- Melbourne, Australia
View attachment 180021
Ron and Allen Lewis Tauranac began building racing cars in New South Wales, Australia during the early 1950's, concentrating on motorcycle engined low budget rear engined race cars that were even then faster than much of the opposition. After Jack Brabham's successes with Cooper in Europe and his decision to go it alone and build Brabham racing cars, Ron Tauranac was asked to join the new venture as chief designer, and the results of that association are now history. Repco Brabhams won the World Championship in 1966 and 1967, and the firm was for a time the world's largest manufacturer of racing cars.
After Jack Brabham retired from the GP circus and went home to Australia, Ron Tauranac stayed on at Motor Racing Developments until Bernie Ecclestone bought the business, leaving shortly after that to setup Ralt and return to building the comparatively low budget race cars that are now produced in ever increasing numbers.
Based on a high-walled straight-sided steel and aluminium monocoque, the RT4 chassis tub features tapered frame extensions that dogleg out sideways slightly ahead of the seat bulkhead, specifically to allow more room to accommodate the engine. The tub also incorporates the mandatory deformable structures of bonded sandwich construction for crash protection, plus two rollover protection structures before and behind the driver, with enough inner space in the side pods to accommodate the rubber bag fuel tanks.
Front and rear suspension layouts are conservative and conventional, with the bulky coil spring/shock absorber units hidden away from the main airstream inside the body. Outboard disc brakes are carried by substantial cast magnesium uprights and feature four spot calipers up front, while two spot calipers work away at the rear. Ducting for the highly effective ground effects aerodynamics is integral with the GRP side panels, which also incorporate the airflow requirements for the mid-mounted oil and water radiators. Normally powered by the four cylinder Ford BDA Cosworth engine and driving through a five speed Hewland FT200 transaxle, Ralt RT4 cars are capable of exceeding 260 km/h.
Year of manufacture
1980-1987
Production total
187
Chassis
Deep sided steel and aluminium monocoque
Front suspension
Independent, earlier versions used fabricated upper rocker arms actuating inboard coil spring/shock units with lower wishbones, later variants actuate inverted coil/spring shock units through pushrods
Rear suspension
Earlier versions used upper A arms and link, lower wishbones and inverted coil spring/shock units. Later variants used rocker arms and inboard coil spring/shock units
Front track
1460 mm
Rear track
1358 mm
Wheelbase
2464 mm
Engine
Ford Cosworth BDA, in-line four cylinder
Bore / Stroke
80.9 mm x 77.6 mm
Compression
13.5:1
Fuel feed
2 x Weber 50mm double choke carburettors
Aspiration
Naturally aspirated
Capacity
1596 cc
Valvetrain
Twin overhead camshafts, operating four valves per cylinder in pentproof combustion chambers
Power
169 kW @ 9200 rpm
Gearbox
Hewland FT 200 transaxle, five speed manual
Brakes
Outboard discs on all wheels, operated by tandem hydraulic system
Wheels
Ralt cast magnesium alloy, 13" x 10" front, 13" x 14" or 13" x 15" rear
Tyres
(F) 13" x 5.20/200
(R) 13" x 6.00/280
Weight
476 kg
http://www.conceptcarz.com/vehicle/z13104/Ralt-RT4.aspx
http://www.racingsportscars.com/type/Ralt/RT4.html
http://rontauranac.com.au/modern-ralt-cars/
http://en.wikipedia.org/wiki/Ralt
Last edited:
