Renault’s new dCi and TCe engines
The new range of Euro 5-compliant dCi diesel engines offers the market's best trade-off between performance and fuel consumption. Like the dCi 90, the dCi 110 and the new dCi 130, all these engines combine fuel efficiency, response and performance without affecting their acclaimed, lowest-in-class noise levels.
The V6 dCi 235 diesel engine, which has been developed for the brand's upper-range models – notably Laguna Coupe – delivers outstanding performance and supreme driving enjoyment.
Thanks to the dCi and TCe line-up, almost 70% of the New Mégane engine range qualifies for the Renault eco² signature, which is a clear indication of their sound ecological and economical credentials.
In order to reduce polluting emissions further in readiness for upcoming European legislation, Renault's engineers are working on other ways of cutting emissions at source thanks to the optimisation of the combustion process and to the introduction of post-treatment systems such as the nitrogen oxide-capturing NOx Trap which will equip the dCi 175 engine.
A further new feature of the powertrain line-up on display is the Renault-Nissan Alliance-developed continuously variable transmission (CVT) which eliminates gearshifts to ensure smooth, sprightly performance and even greater driving comfort. It will be available for the New Mégane range from 2009.
The TCe range
The advent of New Mégane has seen the development of a range of petrol TCe engines which all benefit from the expertise of Renault's engineers in the realm of turbocharging. Known as TCe (Turbo Control efficiency), these feisty turbocharged petrol engines ensure lively, responsive acceleration from very low revs and smooth delivery of power all the way up the rev range. They are economical, too, with running and servicing costs among the best on the market. The TCe line-up comprises three engines: the TCe 100, the TCe 130 and the TCe 180.
The beginning of 2007 saw Renault release the TCe 100 petrol engine which is aimed at its A- and B-segment vehicles (Twingo GT, Clio and Modus). In addition to being a pleasure to drive, this 1,149cc unit returns the fuel consumption expected of an engine of its size, yet features the power of a 1.4 and the torque of a 1.6.
It is equipped with a low inertia turbo and was developed with a view to becoming a benchmark in its class in terms of performance and fuel efficiency. Indeed, its fuel consumption of just 48.7 mpg under the bonnet of Clio III (equivalent to CO2 emissions of 138g/km) makes it particularly frugal and environmentally friendly. The TCe 100 has also been developed in anticipation of the expected upturn in demand for petrol engines following the switch to the Euro 5 legislation. It is mated to a five-speed manual gearbox (JH3) and is manufactured in Douvrin, France .
Renault's latest petrol engine is the TCe 130 (H4Jt) which stands out as a perfect illustration of the expertise the brand has acquired in the realm of downsizing. Although it packs power of a 1.8-litre engine (130hp) and the torque of a 2.0 (190Nm), this new 1,397cc powerplant is particularly fuel efficient and respectful of the environment.
Developed within the framework of the Renault-Nissan Alliance, the TCe 130 benefited from the synergy made possible by the respective expertise of the two manufacturers, namely Nissan's experience of petrol engine development and Renault's know-how on the combustion and turbocharging fronts. Derived from Nissan's normally-aspirated HR15 and HR16 blocks (1.5 and 1.6 litres), this new engine is equipped with an aluminium block and a single-scroll turbo. The profile of the intake ports has been modified in comparison with the normally-aspirated version to encourage the generation of a tumble effect inside the combustion chamber. This ensures a more homogenous blend which in turn favours a more even spread of the flame for enhanced combustion performance. The technique optimises torque at low revs without impairing performance at high engine speeds. The continuously variable camshaft angle at the intake port also contributes to improving performance at all engine speeds and to curbing fuel consumption. To deal with the calories produced by the thermo-mechanical constraints associated with this extra performance and the higher pressures inside the combustion chambers, oil jets are employed to cool the pistons.
The TCe 130 ranks among the best engines in its class as far as running and servicing costs are concerned. Oil change intervals and oil filter changes are every 18,000 miles (or every two years). The air filter and sparkplugs need to be changed every 36,000 miles (or every four years) and the figure for the accessory drive belt is every 90,000 miles (or every six years). This engine drives through a manual six-speed gearbox (TL4) and is manufactured in Valladolid, Spain .
The TCe 180 is a new evolution of the 1,998cc turbocharged petrol block (F4Rt) which provides unrivalled driving pleasure. With torque of 300Nm at 2,250rpm, it is extremely responsive and provides exceptional pick-up from low revs thanks to the combination of its twin-scroll turbo and continuously variable camshaft angle at the intake port which optimises the intake of air into the combustion chamber and enables the turbine to spin up to speed more quickly. The turbo consequently responds to the slightest touch of the accelerator from revs as low as 1,200rpm. The TCe 180 is Euro 5-ready and will equip the New Mégane family. It is coupled with a six-speed manual gearbox (PK4) and is manufactured in Cléon, France .
OCS (Oil Control System) for lower running costs
Following its introduction on the dCi range, the Oil Control System (OCS) is now available for the TCe 100 and TCe 130 engines, too. This feature uses the engine's ECU to calculate servicing intervals as a function of the way the vehicle is used. Should running conditions be considered too severe (e.g. door-to-door type city motoring exclusively), a warning on the dashboard invites the driver to bring forward the next oil change. OCS enables Renault to recommend competitive oil change intervals, while at the same time providing a solution that protects those owners who stray from conventional use. OCS employs an algorhythm which notably takes into account the vehicle's road speed and engine speed. OCS is today fitted to the TCe 100 and is poised to be extended to all the Renault range's TCe and dCi powerplants.
The dCi range
Like its petrol range, Renault's Euro5 diesel blocks have been renamed and are now known as dCi 90, dCi 110, dCi 130, dCi 150 and dCi 180, plus the new V6 dCi 235. Every one of these powerplants features flexibility and a reserve of power from very low down all the way up the revs. Renault's dCi engines incorporate the best technology to achieve the market's best trade-off between performance and fuel consumption. Special care has also gone into minimising running and servicing costs thanks to extended servicing intervals.
The dCi 90 and dCi 110
The 85 and 105hp versions of the 1.5 dCi, which have both been acclaimed for the excellent fuel consumption and equally outstanding driving pleasure they provide, have been joined by two new versions: the dCi 90 and the dCi 110 (depending on market). Under the bonnet of New Mégane, they deliver even better performance, with CO2 emissions of less than 120g/km.
Widely praised for their efficiency and acoustic performance, these 1,461cc powerplants boast torque of 200 and 240Nm respectively and are particularly responsive at low revs. This evolution of the 1.5 dCi features a new fuel return rail and a new control unit for improved fuel efficiency, while the injection pressure has been increased to 1,650 bar and faster sparkplug performance has speeded up starting from cold. To comply with the forthcoming Euro 5 legislation, and in keeping with Renault's stand on the environment, these two engines are equipped with a particulate filter which uses an additional injector located in the exhaust line. This technology is covered by some 30 patents and functions without the driver noticing.
The running and servicing costs associated with the dCi 90 and dCi 110 engines are among the lowest of their class. Oil change intervals have been extended from 12,000 miles to 18,000 miles (or every two years) and the life expectancy of the diesel filter has increased from 24,000 miles to 36,000 miles. The timing belt needs changing every 90,000 miles and no longer every 72,000 miles.
These engines are planned to be B30 biodiesel-compatible in certain countries and will gradually be introduced on Renault models. They are coupled with either a five-speed (JH3) or six-speed (TL4) manual gearbox depending on power output. This Euro 5-compliant diesel block is manufactured in Valladolid, Spain .
The dCi 130
To prepare for the switch to the Euro 5 standard, the dCi 130 engine (F9Q) has been significantly reworked. As a result, this 1,870cc block offers unrivalled driving pleasure. Its peak power of 130hp is available from as low down as 3,750rpm (instead of 4,000rpm previously) and maximum torque (300Nm) is available from 1,750rpm (instead of 2,000rpm). These figures have been made possible thanks to the revised variable geometry turbo with curved blades which contribute to swifter response and the speedier availability of power. The seven-hole injector nozzles (compared with six previously) ensure a finer, and consequently more economical fuel spray. Last but not least, the catalytic particulate filter (regeneration by combustion) and the addition of a new EGR (exhaust gas recirculation) cooler enable it to comply with the forthcoming Euro 5 standard.
These features combine to improve dynamic and acoustic performance, and also optimised fuel consumption, with New Mégane dCi 130 emitting just 135g of CO2/km for a power output of 130hp.
Oil change intervals are now every 18,000 miles (instead of 9,000 miles) and the timing belt needs changing every 90,000 miles (instead of 72,000 miles). This diesel engine drives through a new six-speed manual gearbox (ND4) and is manufactured in Cléon, France .
The dCi 150 and dCi 180
This 1,995cc engine (M9R) is the fruit of a Renault-led Renault-Nissan joint-development and is available with several power outputs, notably the dCi 150 and dCi 180 versions. In addition to combining performance, low noise and respect for the environment, the two versions of this engine are among the most efficient of their class and produce exceptional power outputs of 150hp at 4,000rpm and 180hp at 3,750rpm respectively. Their maximum torque is 340Nm and 400Nm at 2,000rpm respectively and this torque is readily available all the way up the revs to 5,000rpm. Its low inertia variable geometry turbo produces gains in dynamic performance at low revs which is where it really comes into its own. Meanwhile, thanks to their ultra-fast pre-heat sparkplugs, it only takes a press on the 'Start' button to fire up the dCi 150 and dCi 180 engines immediately, even in very cold weather (-23°C).
The dCi 180 is equipped with a particulate filter and a new EGR cooler, and has been engineered for sheer driving enjoyment. In Laguna GT, it returns combined cycle fuel consumption of 43.4 mpg (equivalent to CO2 emissions of 172g/km).
This diesel engine can be mated either to a six-speed manual gearbox (PK4) or to the six-speed auto-adaptive logic automatic transmission (AJ0). It is manufactured in Cléon, France .
The V6 dCi 235
With a power output of 235hp, a generous rev range all the way up to 5,200rpm and peak torque of 450Nm at 1,500rpm, the 2,993cc V6 dCi 235 (V9X) places the emphasis very much on performance. Powered by this engine, Renault Laguna Coupe accelerates from standstill to 62 mph in less than seven seconds.
Derived from the dCi 150/dCi 180 block, with which it shares some 25% of its components, it has been developed to stand out as a benchmark in terms of low noise. It employs high pressure common rail injection with two common rails calibrated at 1,800 bar which feed seven-hole piezoelectric injectors. This technology permits up to five injections per cycle for a higher combustion quality and optimised acoustic performance.
The Renault V6 dCi 235 engine is equipped with a variable geometry turbocharger, a system which yields high torque from very low revs and flexibility at all engine speeds.
The architecture of the exhaust manifolds has been specially engineered to limit load losses and ensure that as much energy as possible is delivered to the turbine. Ultra-fast ceramic technology sparkplugs permit near-instantaneous preheating and starting from cold. Specific work into the calibration of the control unit and the electronic throttle ensure instant engine response. With this engine under the bonnet, Renault Laguna Coupe emits just 192g of CO2/km.
For enhanced reliability and quality, this engine is equipped with two timing chains. Servicing intervals are every 18,000 miles (or every two years). The V6 dCi 235 drivers through the six-speed auto-adaptive automatic transmission (AJ0) and is manufactured in Cléon, France .
NOx Trap: Renault's nitrogen oxide trap
Renault's NOx Trap, a chemical system which traps harmful nitrogen oxides and converts them into a neutral gas, fits perfectly with the firm's resolve to cut polluting emissions. This post-treatment technology has led to 36 patents being filed by Renault and has been running in France and Germany since last month on small company Renault Espace dCi 175 fleets.
The new Renault NOx Trap oxidation catalyser carries out two roles:
conventional oxidation of HCs (hydrocarbons) resulting from incomplete combustion and of CO (carbon monoxide) which arises from incomplete combustion through a lack of oxygen.
post-treatment of NOx (nitrogen oxides), a bi-product of the combustion of diesel fuel at high temperatures.
How the Renault NOx Trap functions
The NOx Trap is based on two alternating phases: the charging phase, which lasts around 10 minutes every 10km, and the purge phase which lasts approximately five seconds. The driver is totally unaware of the process.
During the charge phase, the NOx Trap captures the nitrogen oxides contained in the exhaust gases by means of a porous carrier in the catalytic converter impregnated with platinum, barium, and rhodium. The platinum converts the nitrogen monoxide into nitrogen dioxide (NO2). The barium oxide then captures the nitrogen dioxide molecules to form barium nitrate (NO3)2 which is stored in the trap.
During the purge or regeneration phase, the elements stored in the NOx Trap are eliminated by chemical reduction with the engine running in rich burn mode, that is to say with an air-fuel mixture incorporating just enough air for complete combustion of the diesel fuel. The nitrogen oxides are converted into a neutral gas (chiefly nitrogen). The regenerated NOx Trap is consequently able to pursue its role of trapping more nitrogen oxide.
To ensure the process runs smoothly, additional sensors (oxygen and temperature probes) are positioned in the engine intake and exhaust. The data they collect is transmitted via the CAN to the ECU which controls the NOx Trap.
CVT transmission: for a more comfortable drive
The innovative CVT Continuously Variable Transmission (FK0) was developed by Nissan and is employed by Renault within the framework of the Alliance.
In the case of a conventional automatic transmission, the ability to adapt the point on the engine's operating curve (engine speed and throttle) to the demand for power is restricted by the number of gears (five or six). The continuous variation of the CVT allows the point on the engine's operating curve to be optimized from the fuel consumption, emissions and also acoustic points of view, even during transitory phases. Fuel economy is improved compared with a conventional automatic transmission.
The system delivers an exceptionally smooth and comfortable drive thanks to the seamless acceleration during gearshifts. Indeed, thanks to specific work by Alliance engineers, the CVT proposed by Renault figures among the best of its category in terms of its seamless acceleration performance.
The 2.0 16V (140hp) versions of New Mégane will benefit initially from this technology.
All the engines in the new TCe and dCi ranges are Euro 4-compliant and are already compatible with the forthcoming Euro 5 emissions standard.