The Clio Renault Sport V6 24V was one of the most striking surprises of the 1998 Paris Motor Show and also one of the star attractions of the Renault stand. Described at the time by Renault Sport as a realistic project based on the race-specification Clio Renault Sport V6 Trophy, the road-going version immediately appealed to a broad base of motoring enthusiasts and connoisseurs. On the initiative of Renault Sport, who were at the origin of the project, Renault swiftly reacted to the initial demand for the new model by ordering a preliminary development and production study from TWR (Tom Walkinshaw Racing). The report of the British-based specialist confirmed the feasibility of the project in accordance with the charter established by Renault in the domains of quality, safety and high level road performance. On the basis of these findings, Renault took the decision to produce a limited run of this special 2-seater Clio GT.
The manufacturing process followed this logistic arrangement: the Douvrin factory (Française de Mécanique PSA – Renault) supplied the engines, the Renault factories at Cléon and Flins supplied the gearboxes and the body in white with its hinged attachments. The Grand Couronne site collected and delivered those parts from the range which were not specific to the Clio Renault Sport V6. All the necessary bodywork modifications, and then final assembly, were carried out by hand on the TWR site at Uddevalla in Sweden.
Renault’s designers gave the car a unique style, expressing its philosophy: playful and powerful, but also civilised and accomplished. The V6 was wider (+ 171 mm) and lower (- 66 mm) than a standard Clio. Although the body shell, bonnet panel, roof and rear hatch were taken from the Clio Renault Sport 2.0 16V, the bumpers as well as the front and rear wings were specific, while the sill panels and body sides were provided with composite covers. These body-coloured special parts were completely integrated into the car’s design and endow it with a sporting appearance. Borrowed from the world of competition, the design of these parts also contributed to the efficiency of the vehicle by improving aerodynamics and cooling.
The wide front spoiler together with the discreet spoiler above the rear hatch increased downforce and therefore roadholding. The heavily perforated front bumper admited air to the radiator, while the widened front wings reflected the appearance of F1 side pods, with integral air intakes to ventilate the engine compartment. The left-hand intake was also connected to the induction system and assumed the role of dynamic air intake. Other sports-type features included the fuel filler cap, the twin round stainless steel exhaust pipes emerging from the centre of the rear bumper, the honeycomb grilles around the rear silencers, the front foglamps and the cooling air intakes in the front bumper.
The 38mm increase in wheelbase, and widening of the front track by 110mm and the rear track by 138mm, placed the wheels at the four corners of the car, ensuring its balance and extremely good dynamic behaviour. The calibration of the dampers and the choice of spring rates guaranteed comfort and dynamic behaviour worthy of a Grand Touring car. The 17-inch OZ “Superturismo” light alloy wheels were shod with Michelin Pilot Sport tyres, with dimensions 205/50 at the front and 235/45 at the rear. The structure of the tyre was specially developed to fully exploit the potential of the Clio Renault Sport V6 chassis.
The braking system included four ventilated disc brakes, 330mm in diameter at the front and 300mm at the rear, with separate front/rear double circuits assisted by twin 7’’/8’’ servo units. Developed for competition, the 4-piston AP Racing front calipers were used for the first time in a “production” car. They were notable for their lightness and for their exceptional resistance to heating, thanks to external high-pressure hydraulic lines which ensured optimum cooling of the brake fluid. The 4-sensor Bosch 5.3 ABS completed the configuration of the Clio Renault Sport V6 braking system.
The Clio Renault Sport V6 was built around the 3.0 V6 24V engine (L7X 210bhp). Installed tranversely in the mid-rear position, it delivered 230bhp. Power was transmitted to the rear wheels via a new 6-speed manual gearbox. The powertrain provided all the driving pleasure appropriate to a Grand Touring car, with a flexible yet powerful engine, delivering the feeling of acceleration even from the lowest speeds. Top speed was 235 km/h, acceleration from o to 100 km/h took 6.4 seconds and the 1000m standing start 26.5 seconds.
The engine specialists at Renault Sport made many changes to the 3.0 V6 24V engine to improve performance while retaining ease of driving. Changes to the induction, pistons and injection enabled the output to be raised to 230bhp at 6,000rpm with a maximum torque of 300Nm at 3,750rpm (compared with 210bhp at 6,000rpm and 285Nm at 3,750rpm), while continuing to comply with the Euro 3 emission standards. The engine specialists achieved the gain in power by increasing the compression ratio and improving the gas flow within the induction and exhaust systems. Variable inlet valve timing with two camshaft variators (one per cylinder bank) allowed the engine to work with two different valve timings according to operating condition, while the standard motorised throttle valve of the the V6 was retained.
The specific pistons had a different shaped crown which resulted in a higher compression ratio (11.4 instead of 10.9) while maintaining combustion quality. The specially developed exhaust system reduced back-pressure at the engine exhaust ports. Its symmetrical form, as well as the unique high-volume silencers resulted in better performance and a more pleasant sound. The speed limiter setting was increased by 500rpm, from 6,600rpm to 7,100rpm. The engine flywheel was lightened in order to enhance the speed of engine response. Cooling was also especially carefully developed, with a big enough radiator. Apart from the scoops on each side of the car, the fairings beneath the body were also designed to assist ventilation of the entire powertrain assembly.
The Clio Renault Sport V6 was fitted with the new 6-speed manual gearbox known as the PK6. With short selector movements and great precision of operation, the PK6 provided the characteristics of a sports gearbox while offering a comfortable use. The 6th gear made long journeys more pleasant by reducing both noise levels and fuel consumption. The PK6 gearbox was basically a rework of an existing 5-speed unit but equipped with a completely new internal control mechanism. Selector precision was improved, while selector effort was reduced by 30% and lever movement by 15%. Mechanical friction losses, meanwhile, were reduced by 20%. As a measure of its technical performance, the PK 6 gearbox was 2kg lighter than the previous 5-speed unit from which it was developed. PK6 was also sufficiently compact to allow its installation with the transverse V6 engine in the Clio Renault Sport V6.