Following its unveiling at the Moscow motor show, we now have more details of the global-market Toyota Camry XV50 facelift and in particular, its new 2.0 litre four-cylinder engine.
New 2.0 litre engine with VVT-iW, D-4S and EGR, mated to six-speed auto
The 1,998 cc, Euro 5-compliant engine features VVT-iW (Variable Valve Timing-intelligent Wide). VVT-iW debuted on the Lexus NX 200t's direct-injected 2.0 litre turbo 8AR-FTS engine, enabling it to run in both Otto and modified-Atkinson cycles.
At low loads, the VVT-iW-equipped engine is capable of switching to a modified-Atkinson cycle to boost fuel economy. At higher revs, the engine can return to the Otto cycle for enhanced power delivery and performance. VVT-iW features standard VVT-i on the exhaust valves and VVT-iW on the intake side. The latter features a mid-position camshaft lock mechanism which retards the continuously variable valve timing.
For the new Camry, combined with a six-speed Multi-mode automatic gearbox (bye bye four-speed auto!), Toyota claims a fuel economy figure of 7.2 litres per 100 km - a 13% reduction over the outgoing 2.0 litre engine.
With a 12.8:1 compression ratio, the engine develops 150 PS at 5,600-6,500 rpm and 199 Nm of torque at 4,600 rpm. As a result, the new Camry sprints to 100 km/h from rest in 10.4 seconds before hitting a 210 km/h top speed.
There's D-4S too, which means separate twin injectors for both direct and port injection. Depending on engine speed, high-pressure direct injection into the cylinder and conventional intake port injection, or direct cylinder injection only. Hence, intake air and fuel are mixed evenly at all engine speed ranges, increasing throttle response, power and torque over a wide range of engine speeds without sacrificing fuel efficiency and environmental performance.
The engine is also fitted with a water-cooled Exhaust Gas Recirculation (EGR) system, combining an EGR cooler with an electronically-controlled EGR valve to give optimum control of the EGR gas flow volume for equal distribution to each cylinder, enhancing fuel economy.
Other improvements include optimised shapes of the cylinder head intake port and piston (creating tumble flow for better combustion), better cooling for the cylinder block, cylinder head and piston oil jet, plus an optimised taper squish shape to improve anti-knock performance.
An offset crankshaft reduces the piston thrust load to lower friction losses. Allied to enhanced cylinder bore roundness, a resin coating to the piston skirts and lower tension piston rings reduce friction losses from the rotating parts. And the adoption of roller rocker arms and a low friction timing chain further reduce valvetrain friction losses.
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