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Toyota Applying Optimal Drive Technology in New Urban Cruiser

The Urban Cruiser. Click to enlarge.

Toyota is applying its gasoline and diesel “Optimal Drive” technology in the new B-segment hatchback crossover Urban Cruiser, unveiled as a design preview at the 2008 Geneva Motor Show (earlier post) and in a production version at the Paris Motor Show in October 2008 (earlier post). The Urban Cruiser begins arriving in UK showrooms in May.

The gasoline option is a 1.33 Dual VVT-i 2WD model with Stop & Start that emits 129 g/km of CO2. The diesel option is a 1.4 D-4D AWD model; with CO2 emissions of 130 g/km, it offers the lowest CO2 emissions of any four-wheel drive car using an internal combustion engine, according to Toyota.

The 1.33-liter VVT-i engine. Click to enlarge.

1.33 Dual VVT-i. The Urban Cruiser follows its Auris and Yaris sister models in adopting Toyota’s new 1.33 Dual VVT-i engine, equipped with a Stop & Start system. Stop & Start turns off the engine when the car comes to a halt, the gear shift is moved to neutral and the clutch pedal is released. Automatic restart is instantaneous as you engage the clutch again to select a gear ready to pull away. This has a significant impact on fuel consumption and emissions and can achieve a reduction of up to 4% in urban driving.

The 100 bhp (75 kW) engine in the 2WD Urban Cruiser emits 129 g/km of carbon dioxide and has an official combined cycle fuel consumption of 5.5 L/100km (43 mpg US). The engine’s design benefits from Toyota’s motor sport experience in being exceptionally lightweight and compact, with a small bore and long stroke, giving a very high power to weight ratio.

Further engine efficiency has been achieved by the reduction of friction throughout the new powertrain range. Revised roller rocker technology incorporates new camshaft profiles for friction reduction in the valve gear. Enhanced bore circularity and lightweight, coated pistons reduce friction in combustion chambers. Increased engine block rigidity, the adoption of a water jacket spacer and the use of low-viscosity oil further reduce mechanical friction.

Engine efficiency is enhanced through a high, 11.5:1 compression ratio, the refinement of intake port and combustion chamber design, and the introduction of piston cooling by oil jet.

Toyota’s Dual VVT-i valve timing helps boost response across the entire rev range, improving torque at low and medium engine speeds while at the same time reducing emissions and contributing to better fuel efficiency.

1.4-liter D-4D. Toyota is also offering a comprehensively revised version of its 1.4-liter D-4D common rail diesel engine in Urban Cruiser, exclusively with all-wheel drive. Equipped with the latest piezo-electric injector technology and a diesel particulate filter (DPF), it produces 130 g/km of CO2.

The piezo-electric injectors work at exceptionally high pressure and can supply larger, more precise volumes of fuel at twice the speed of conventional injectors. This means they can deliver multiple injections in each combustion cycle, giving responsive engine performance with low fuel consumption and reduced emissions.

The engine generates 89 bhp (66 kW) at 3,800 rpm and 205 Nm (151 lb-ft) of torque between 1,800 and 2,800 rpm, with combined cycle fuel consumption of 4.9 L/100km (48 mpg US).

Both engines use a new six-speed transmission, which also benefits from the application of Toyota Optimal Drive technology. Gear changes are quiet and smooth and a wide sixth gear ratio helps the powertrain achieve world-class levels of efficiency and fuel economy.

Toyota has cut the quantity of harmful volatile organic compounds (VOCs) used in Urban Cruiser’s interior parts, and used acrylic-based material for the undercoating in place of polyvinyl chloride.


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