Motor Racing Developments (MRD)/Ralt racing record 1975-1993
RT1. A single aluminium alloy monocoque with rear tubular subframe served for all three categories in which the RT1 ran. Additional deformable structures were added when demanded by a category and the fuel tanks were in side sponsons, right hand only for Formula Three, both sides for Formula Two, A wider cockpit surround, always part of the original design was held back until the car proved itself through fear of negative customer reaction.
Front suspension was by outboard coil springs and double wishbones, rear suspension was by a lower wishbone, a single upper link and twin radius roads.
*Cars supplied for use in Formula Three had a slightly narrower track than 1975 cars.
One of the Formula Atlantic RT1s was fitted with an enveloping body by Tony Cicale and run in the Can-Am Challenge where most competitors used 5-litre engines.
RT3. Ground effect car with an aluminium monocoque with honeycomb bulkheads, inboard suspension all round (for the first time on a Tauranac car). a central fuel cell and a Hewland Mk 9 gearbox.
In 1979 an RT3 was run in Britain only by Eliseo Salazar and then unsuccessfully. The car needed development, especially in the area of aerodynamics.
The simple sheets which formed the sliding skirts were made of plastic, for low friction but, at speed skirts were sucked in by the low pressure area they were helping to form beneath the car. This cause them to stick, giving both variable downforce and centre of pressure.
RT2. A Ground effect Formula Two car made exclusively for the use of the Toleman team, but very much on the same lines as the RT3/4. Toleman’s designer, Rory Byrne, was consulted during the build phase. During the season the team incorporated its own modifications.
For 1980, Toleman built its own version of the RT2, using higher grade materials than Ron Tauranac felt necessary and duly took 1-2 in the Formula Two Championship.
In 1981 Lola built customer versions which were sold as Toleman T850s – although how Toleman could ask Lola to build a Ralt is another matter. Stefan Johansson won races in one.
SPA Fabrications later acquired surplus monocoques and spares from Lola and these became the basis of the successful Rowan hill climb cars.
The RT2 had an eventful life under its various guises.
RT4. Another variation of the RT2/3 which used the Ford BDA engine. Ray Mallock used both an RT1 and an RT4 to win the British Atlantic series.
RT4. One RT4 appeared occasionally in Formula Two events. The Championship was won by Toleman, using a development (the TG280B) of the Ralt RT2s which the team had run in 1979. Lola Cars also made examples of the Toleman for customers
RH6. The RH6 used a V6 Honda engine as a stressed member and was run exclusively by the works for Nigel Mansell and Geoff Lees. Its highest finish was second (Mansell) at Hockenheim.
RT2. A single RT2-Hart, given an enveloping single-seater body, was run by Gary Gove in the Can-Am Challenge and finished 11th.
The main change on customer cars was the adoption of pushrod front suspension.
The RH6/82, however had an aluminium honeycomb monocoque and the cockpit was further forward than previously. The suspension was changed and the rear track was much wider.
Again, only minor changes for the customer cars, but the RH6/83 had a revised monocoque, wider front track with pullrod suspension, Michelin tyres and 340 bhp with a much more usable rev range.
Only minor modifications to the junior formulae cars, the main one being that more customers specified a Hewland FT200 gearbox.
The RH6/84 was close to the minimum weight limit of 515 kg, there was slightly more power and a Jabroc (laminated wood) understrip to maintain the 4cm clearance rule.
Team Ikuzawa ran an RH6-Honda with some success in the Japanese Championship.
1984 saw the last year of the European Formula Three Championship which had begun in 1975. A total of 130 races were run and Ralts won 50 of them, more than any other marque.
RT30. New ‘flat bottom’ regulations and new rules about width demanded a new car. The monocoque RT30 was along the lines of the RT3, aluminium with a honeycomb front bulkhead and a tubular frame to support the engine, but the suspension was pushrod all round with the rear springs on top of the gearbox.
The most surprising thing was its asymmetrical body, it had just radiator, on the left hand side, with a low mandatory side protection panel jutting out from the right hand side.
Glenn Waters’ company, Intersport, offered a body kit to convert existing RT3s to comply with the new rules – 48 kits were sold.
RB20. For the new ‘flat bottom’ 3-litre Formula 3000 which replaced Formula Two, Ralt carried on development of the RH6/83. The the ‘RB’ designation referred to Bridgestone, which sponsored the team.
On the chassis, major difference was the use of pushrod suspension at the rear with the springs mounted on top of the gearbox, as they were on the RT30.
Cosworth DFV engines were used by everyone, but restricted to 9,000 rpm by a rev limiter so they gave about 125 bhp more than an Formula Two engine had.
RT30. The only major modification was to take the rear springs from their position on top the the gearbox and mount them vertically on each side of it.
RT20. Ralt abandoned the all-honeycomb monocoque and reverted to sheet aluminium with honeycomb bracing. There was also a new pushrod front suspension layout with the springs mounted horizontally over the driver’s legs.
Works cars used a new Honda V8 engine which was actually designed by John Judd and Neil Walker at Engine Developments. This was lighter than the Cosworth DFV and the Hewland FT200 gearbox was lighter than the FGB transmission used in 1985. The car was under the weight limit so could be ballasted to best effect. Customer cars used DFV engines and the only race won by the works was Mike Thackwell winning at Pau.
RT31. A greater use of honeycomb made the monocoque stiffer and a repositioning of the front spring units allowed a slimmer profile than before.
RT21. The monocoque was stiffened not only by more honeycomb, but by the judicious used of carbonfibre. There was new pushrod front suspension but the previous pullrod rear layout was retained. The works used Judd/Honda engines, customers used Cosworth DFVs.
RT32. Engines were mounted 30mm lower and Hewland produced a new magnesium gearbox casing. The monocoque was new with a honeycomb lower half riveted to a carbonfibre top. There was pushrod suspension all round and, because the Speiss-developed VW engine had been marginal on cooling, there was a conventional two radiator layout.
RT22. This combined an all-new carbonfibre monocoque with the proven suspension of the RT21. In testing, however, it experienced severe traction problems and the designated works drivers took their sponsorship elsewhere. Only one sixth and one fourth place was achieved and the works Ralts did not complete the Formula 3000 season.
This was the major reason why, in October 1988, Ralt was able to be acquired by March Group plc.
BT33. This followed the RT32, but had an even cleaner shape and also benefited by detail revisions to the aerodynamics such as new profiles in the sidepods.
RT35. The RT35 was the final expression of a line which began with the RT32. It was the last Formula Three car that Ron Tauranac designed for Ralt of his own volition.
In 1991 March/Ralt was the subject of a management buy-out from March Group plc, and the new company was known as March Cars Ltd.
RT40. Designed by Ron Tauranac while Andy Thorby designed the RT36.
RT24. Simtek update of RT23. Only one was known to have raced. The production figure of two cars is a reasonable guess.
After 1993, Ralt production figures become a little hazy. The best information is that a total of 32 Ralt RT41s were made to April 1998. Twelve cars were made in 1994, nine in 1995 and five in 1996. That makes 26 which gives a shortfall of six cars which were made in 1997/8. Ralts dominated the Toyota Atlantic Championship in 1997 despite Swift receiving the contract to supply new cars to the series.
This indicates a total for Ralt of 1083 cars and Ron Tauranac takes credit for 1047 of them.
To complete the record, the following championships were won by drivers using Ralts:
In early 1993, March Engineering Ltd. was taken over by Andrew Fitton and Steve Ward. Ron Tauranac was retained as a part-time consultant, working mainly on the Formula Atlantic cars, but the arrangement did not last long.
In 1993 Ralt took not take a single Formula Three win and the two cars which started the season in Britain were soon exchanged for Dallaras. Apart from the first five races of the British series, which were taken by Reynard, Dallara took every win in the main Formula Three Championships.
Joe Zeller, a Swiss, did reasonably well on his home patch with a Ralt RT37.
Two examples of a new Ralt, the 94C, designed by Chris Radage, appeared in Britain for the first few races of the 1994 season, proved uncompetitive and were abandoned. By then Ron Tauranac had left the company.
Soon afterwards, Andrew Fitton and Steve Ward split, with the former taking the remaining assets of March and the latter continuing to build and service Ralt RT41s for the Toyota Atlantic Championship.
With thanks to Mike Lawrence, the author of Brabham+Ralt+Honda, for the information provided above.