During discussions, engineer Christophe Chapelain asserted that a Clio chassis would be perfectly able to handle the performance levels of a 300bhp engine, based on his experience in rallying. One thing led to another and the idea of a Clio R.S. with exceptional performance gained ground.
"We all recalled the impact made by Clio V6. We wanted to create a technical concept car with extraordinary performance levels but which was more realistically priced. We therefore had to keep our feet on the ground and use simple, ingenious solutions to achieve a vehicle that could be type-approved. Furthermore, we wanted this project to be entirely developed by Renault Sport," recalled Patrice Ratti. "In theory, a Clio R.S. fitted with our most powerful engine – the 275bhp, 2.0-litre turbo engine – was an attractive proposition, but we had to conduct more serious checks as regards its feasibility. In less than a month, a small team had completed a preliminary study that confirmed it was possible to house this engine under the bonnet. We therefore decided with Thierry Landreau, Technical Director of Renault Sport Cars, to take a gamble and actually produce this car. Overall coordination of the project was placed in the hands of François Ratinet, who led the ’commando’ team, which I supervised."
Michael van der Sande, at the time Senior Vice-President, Renault Group Marketing, was also excited about the idea. Renault was studying its return to Formula 1 and Clio R.S.16 would further demonstrate the close ties between racing and production cars. At the end o December, Renault gave the go-ahead for the project.
“Without giving away all our secrets, I can tell you that we’ll have a great surprise for everyone at the Monaco Grand Prix. They will see just how Renault Sport makes the connection between the racetrack and the road.”
Jérôme Stoll – President of Renault Sport – 3 February 2016 Launch of the Renault Sport Formula One Team
It was decided that Clio R.S.16 would be unveiled to the public on Friday, 27 May 2016, at the Monaco Grand Prix. This deadline determined a large part of the project, which therefore had to be completed within just five months !
“For this project, the racing engineers have introduced new working methods. With the main constraint being the tight deadline, our teams managed to learn to do without the numerous iterations that are typically involved in designing a production car, while still maintaining the same levels of quality and performance. In future, our aim will be to use this experience to design other slightly crazy cars, which will help us to add to our expertise whilst exploring new avenues for the future.”
Patrice Ratti – Renault Sport Cars Managing Director
A commando unit
A team of a ten or so people was put together in early January at Renault Sport. The project was entrusted to the Preliminary Project unit, a Prototype Build Centre department.
"The premise was to design an exclusively Renault Sport vehicle, fitted with the most powerful engine in the range," explained Laurent Doré, Manager of the Prototype department. "The aim was perfectly clear, but the first difficulty concerned the lead-times, which were extremely tight. We created a team made up of experts from Renault Sport Cars and Renault Sport Racing. This little ‘commando’ unit was managed by Maurizio Suppa, an engineer specialising in prototype design. "
Whilst remaining independent, the Preliminary Project unit could nonetheless use the many skills found at the Les Ulis and Viry-Châtillon sites (Essonne). The project immediately garnered the support and enthusiasm of all of those involved in the project.
Many challenges to be met
Aside from the time constraints involved in completing its work, the Preliminary Project unit quickly identified the major challenges posed by the specifications. Firstly, it was a question of correctly positioning the engine, gearbox and cooling system taken from Mégane R.S. 275 Trophy-R.
With some 360Nm of torque, the engine required the powertrain suspension to be altered, and the teams came up with an inventive solution, combining and adapting parts taken from the production Mégane, Kangoo and Espace.
In order to provide optimum cooling, considerable simulation work was done in conjunction with the design engineers, who were tasked with revising the front end of the vehicle. These calculations were also intended to define settings that would enable Renault Sport’s trademark impeccable road-holding to be maintained.
Another key element as regards performance, the exhaust system had to be revised to meet the engine’s output requirements. Without changing the route of the exhaust line under the car, the increased permeability of the system enabled the engine designers to meet their targets. The acoustics were not overlooked either : following track testing, Clio R.S.16 was fitted with an Akrapovič twin-exhaust silencer, which produces a rather pleasant sound.
Although it isn’t the most visible point, the electronics also required careful consideration, because the systems used on Mégane R.S. 275 Trophy-R and Clio R.S. are not based on the same architecture. Engine data is, however, essential in ensuring the ABS and ESP work properly, and vice-versa. The challenge was met by incorporating gateway software in the ECU of Mégane R.S. 275 Trophy-R, which interfaces with Clio’s systems.
Chassis and suspension systems that deliver their full potential
With some 35 years’ experience at Renault Sport, Pascal Auffrère was asked to work on the design of the front axle : "This project was given to me because I’ve been here for such a long time. Having worked on rally cars until the mid-90s, I moved over to production cars when we began designing Clio II Renault Sport. The Clio R.S.16 project was exhilarating because we had to work extremely quickly to produce a car with exceptional performance levels. It was easy, really, that was all I thought about ! When conducting research and preliminary studies for a front axle capable of handling the stresses created by the power and torque of the engine, our knowledge of what had already been done at Renault Sport helped to save time. We started with the independent steering-axis front suspension, for which we designed a new stub axle. Cut from the block, this beautiful aluminium part enabled us to obtain the suspension layout we were after and to align it with the positioning of the steering."
Clio R.S.16’s damper system uses Mégane R.S. 275 Trophy-R’s one-way adjustable shock absorbers, with sliding cartridge. The braking system is also derived from Mégane, with 350mm-diameter steel discs fitted on aluminium bowls.
"Generally speaking, we tried to reuse the innovations that were introduced on Mégane R.S. 275 Trophy-R," emphasized Maurizio Suppa. "For example, we used a lithium-ion battery, which saved around fifteen kilos and space in the engine compartment !"
The design of the rear axle proved to be much more straightforward, because it was taken from Clio R3T, the rally version of Clio R.S. "In line with FIA regulations, we started with the production component, which was reinforced by a series of joint-welded bulkheads. To cope with the stresses of the roughest gravel rallies, we have increased roll rigidity by over 50%. We are therefore certain it will prove an effective solution for Clio R.S.16 on the road," detailed Christophe Chapelain.
Another major challenge arose when trying to work out how to fit 19-inch wheels on a bodywork designed for 18-inch wheels. The solution involved trimming the wings slightly, which were then fitted with composite fibre flares.
Clearly, all this technology must be contained within a cover that reflects the ambitions of Renault Sport. The exterior design of Clio R.S.16 was highly important, not least because it had a significant influence on the cooling performances of the car.