Your servant interviewed Ralph Berg, Technical Training Manager of Toyota Belgium on new ecologic technologies...  

The latest Brussels Car show edition 2009 sported a central theme – as could be expected – on environmentally friendly cars, and we took the occasion to make some interviews about the topic with several major manufacturers.

We started our tour at the Toyota stand, where the besides the new iQ , Avensis a special display was mounted to present the Toyota Optimal Drive. We talked here with Toyota Belgium Technical Training Manager Ralph Berg.

Toyota Optimal Drive covers a range of different technologies to improve environmental performance of its cars, and the results are impressive to say the least, and a harbinger of the level of high-tech solutions we will see on mass produced cars in the (near) future, providing the competition matches Toyota’s formidable technological skills .

Toyota shows its permanently engaged starter motor gear behind the perspex casing to show the public how its Stop & Start technology works...

Toyota goes a different route than other car makers which offer special “eco” equipment models, with lower-powered engines and modified equipment. The Japanese manufacturer makes the improvements throughout the model range, and is keen to avoid any loss in driving pleasure on its cars, just by the fact that they are “eco.”

All new Toyota models will soon benefit from Toyota Optimal Drive, with new iQ, Avensis and Auris/Urban Cruiser 1.33 Stop&Start leading the way.

The starter motor is permanently erngaged for smoothly starting the engine in traffic jams by simply pressing the clutch pedal...

The Stop & Start technology deserves some special comment. In a world-first design, Toyota adopted a permanently engaged starter gear mechanism: the starter motor is in direct contact with the ring gear on the engine, which means the engine stops and starts quickly and quietly. During engine operation, the starter gear mechanism is freewheeling from the engine ring gear. But when the engine has come to a standstill and has to be started again, the permanently engaged starter mechanism starts the engine fast and smoothly. Taking the Auris/Urban Cruiser as an example, compared to the 1.4 VVT-I version, the start-up noise level has been reduced by 9dB and starting time cut from 0.7 to 0.4 seconds. According to Ralph Berg, this setup reduces driver irritation caused by the starter motor noise when one has to restart several times in short intervals in traffic jams. We could not agree with him more. This frequent engine noise starting causes us to cut out the offered start/stop systems on our test cars all too often…

A model displayed on the show the functioning of variable valve opening with variable valve timing combined, warranting optimal combustion for its new petrol engines...

State of the art engine design with the new Valvematic Engines…

The new Avensis Range is offered now with another engine novelty: the Valvematic, an evolution of the VVT-i mechanism which now incorporates continuous valve lift control together with VVT-i’s existing valve timing control. Valvematic also eliminates the need for a throttle valve: the volume of intake air can now be controlled using valve lift instead. The technology was first revealed already by Toyota in the middle of 2007.

By the way, Toyota is of course not alone in offering this technology. Honda also has engines with continuous valve lift control combined with variable valve timing, a technology it calls AVTEC.

Valvematic is offered on the 1,6 and 1.8 to 2.0 litre petrol engines of the new Avensis, and we are of course keen to test how these new power units behave in everyday traffic. Torque in lower and mid rev ranges is markedly improved, as is fuel efficiency, CO2 emissions and power. Ralph told us that many drivers have come to expect more torque from Diesel engines, and modern petrol engines have to meet these requirements.

On the Brussels Salon, Toyota had some interesting engine cut-outs and films on display of these new Valvematic engines, where the visitor could get visually acquainted with the new technology.

The variable valve lift/opening makes a trottle valve superfluous, but optimisation of the length of the induct tract is "de rigueur" to achieve good engine torque and efficient combustion...

Lighter, more compact and offering less internal friction… the new 1.33 Dual VVT-i engine.

The all-new 1.33-litre Dual VVT-i engine is the latest step in Toyota lightweight engine  technology. Toyota’s motorsport experience, where compact and powerful engine design is crucial, shows in its design: the new unit is 54mm shorter and 127mm narrower than the previous 1.4-litre VVT-i and weights 13kg less. The result is a four-cylinder engine that is the same size as a three-cylinder 1.0-litre VVT-I, found in the iQ. Its small bore and long stroke design, which is also excellent for torque, gives a narrow block and reduces weight to give a very high power-to-weight ratio.

New pistons were developed with a smaller contact area to reduce internal friction. Piston weight was also significantly reduced, from 280g to 180g – a 36 per cent saving – which means they use less energy to move. An oil jet was integrated into the design, cooling the piston, enabling a higher compression ratio to be used with ordinary 95 octane fuel: not less than 11.5 to one!

Toyota reduced internal friction further by introducing a roller-type valve rocker, and lightening the parts of the valve train.

The iQ was on the show...

Progressive Diesel technology…

The  1.4 D-4D engine uses now Bosch Piëzo injectors with 1800 bar pressure, the compression having been lowered to 16.5 to one offering better thermodynamic efficiency.

The turbo uses variable geometry, and one should not forget the Toyota D-Cat technology, reducing the NOx emissions to a level which lies well within the Euro 5 Norm with 0.12 grammes of NOx per km. Ralph Berg reminded us that NOx emissions are about 30 times more obnoxious than CO2 for causing the greenhouse effect.

We will soon tell you more about Toyota’s new technologies when we have driven the cars, so read more on these pages soon, but on these pages you will soon read the test of another Toyota Icon, the Hilux II Pick up!

Hans Knol ten Bensel

The new Valvematic technology is offered on the petrol engines of the New Avensis. We are keen to test these powerplants soon...