19 October 2017

Variable valve timing

According to Wikipedia, variable valve timing (VVT) is “the process of altering the timing of a valve lift event, and is used to improve performance, fuel economy or emissions”.

 

A combustion engine takes in air to the cylinder chamber and gives off exhaust gases by means of valves which open and close the intake and exhaust passages. Variable valve timing changes the manner in which the intake and exhaust valves work at different engine speeds – helping to improve the engine’s performance and fuel economy and emissions by enabling the optimisation of engine performance under different loads and operations. As an example, a low engine speed valve timing can be advanced to help throttle response and engine torque, whilst under load. Valve timing can be retarded in order to reduce exhaust emissions and increase power at higher RPM, where valve opening times are greater.

 

Although VVT was first patented by Fiat in the late 1960’s, the first production vehicle to be made available to the market with a VVT system was the Alfa Romeo Spider 2000, released in 1980. Since then, many motor manufacturers have adopted the technology, with implementation variations and different names – for example Toyota has VVT-I or Variable Valve Timing with Intelligence and Honda has VTEC (Variable Valve Timing and Lift Electronic Control – but they are all based on the same underlying technology.

 

Engines without VVT have a non-adjustable camshaft, with fixed valve movement duration and timing.

 

A rotating camshaft sits above the valves and controls the opening and closing of the valves. The technology controls the timing or points in the piston’s movement at which the valves open and close, how long the valves stay open and the size of the opening. Sensors measuring airflow and camshaft position feed information to the engine control unit (ECU), which controls the valve movement.

 

Using the camshaft to control the opening and closing of the valves does limit the variability of the valve. Better engine performance would be possible if we were able to directly control each valve – and this is where the future lies for this technology.

 

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Carbiz Statement on War in Ukraine

In the past century, few nations have suffered more than the people of Ukraine. During the Second World War, the country, including its capital, were ravaged by the forces of Nazism. 2,000 mass graves of Ukrainian Jews remain throughout the country as evidence of a barbaric and shameful past.

Aside from the devastation caused by invasion, we remember the millions of Ukrainians who died in the famine imposed on Ukraine in the 1930s through the Stalinist policies directed against the peasantry from the Kremlin. This is one of the great crimes of modern history and is so often forgotten.

With this bloody history in mind, today we watch with anguish and despair as the people of Ukraine are invaded once more. Once again, we see needless suffering from policies directed from Moscow. Ukraine is facing loss of life, the prospect of loss of land, and loss of freedom.

Ukraine is a sovereign state and its people have the absolute right to determine whether their future lies in closer ties with Europe and the US or with Russia. The Russian Federation has sought to justify the military conquest of another state’s territory on the basis that they are protecting inhabitants of the same ethnicity allegedly suffering persecution. The use of this narrative as a pretext for invasion has a dark and sinister history.

It is difficult to comprehend how such acts could even be contemplated by the Russian Federation, which has itself suffered so greatly and sacrificed so immensely in the struggle against foreign invaders. Russia's history is of finishing wars not beginning them, protecting their land and their people against the tyrannical aspirations of would-be conquerors. This is a glorious history of which the Russian people are justifiably proud. Yet today, Russia is the aggressor and its actions violate the most basic norms of international law and breach international peace and security.

We also watch with admiration as Ukraine’s president, Volodymr Zelensky demonstrates the very best of Ukraine and of leadership. His refusal to allow his nation to be consumed by a great military power, his refusal to evacuate himself and his family despite credible reports of assassination plots, his willingness to place himself on the frontlines to bolster the moral of his forces and his people, are truly inspiring. President Zelensky’s Jewish background show the new tolerance and diversity of Ukraine and its reconciliation with a troubled and complex past. President Zelensky has been lauded as the new leader of the free world, and he inspires us all to stand tall in the face of overwhelming force, to remain close to one’s people, to be guided by principle and integrity, and to fight with courage.

We hope that this war comes to an immediate and lasting end. We hope that a ceasefire can take effect to protect civilian life and infrastructure. And we hope that fruitful negotiations are commenced and successfully completed. We deplore the bloodshed and suffering needlessly imposed on the Ukrainian people. And we extend our solidarity to Ukraine and its people throughout the world during this most difficult time.

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Toyota Kluger Hybrid

So you've got a partner, a dog, two point five kids, a good job, solar panels on the roof, and need a reliable modern car. Without any fault of your own, your pride and joy big SUV has just been centre-punched by some red light runner.

So what comes next? You have a choice of rental car, to be paid for by the at fault drivers insurance provider. Obviously something in the same class. What do you choose? Something like a seven seat Toyota Kluger? Save the day the Carbiz way!

The Toyota Kluger hybrid? Lets have a look at it. First off, its a very utilitarian efficient vehicle, that does not stand out. But you know it has the legendary Toyota reliability and toughness. You are not trying to impress the neighbours, you just want comfortable reliable transport that is non-polluting, quiet and comfortable, and has all the electronic bells and whistles that will keep the kids amused.

The Kluger sits midway between the smaller Toyota cars, and the very popular rugged Land Cruiser models. It is notably quiet to drive, and just feels so smooth and easy to drive. You sit higher than in a regular small car, which is very nice in heavy traffic conditions.

Much of the time in traffic it will be running on its electric motor, but you have no worries about range as in an all-electric car. The Toyota's hi-tech 2.5 litre 4 cylinder petrol engine will kick in as required, either to supply extra power when needed, or to charge the battery in continuous slow traffic. The absolute best of both. You are not trying to make a statement, as in buying a pure electric which might run short of power just when the kids need to be somewhere, like half an hour ago.

Safety is top class, with seven airbags, and an array of semi-autonomous safety functions that virtually take control of the car if it detects an object like a cyclist, or strays from its lane. With its detection systems, it almost has a spatial aura all around it that enables it to escape if that space is violated.

Plenty of cargo space for junk, rides well, not at all harsh, ticks all the boxes really. Resale value is not an issue. Perfect!

And if after a taste you decide that an outback holiday adventure sounds like a good idea, you're ready. I know of people who have driven their Kluger to Birdsville on a camping trip. It rode the stoney roads very well, allowed zero ingress of dust, and came home ready to do it again. While the Land Cruisers might be the true outback tool for the Simpson Desert, the Kluger is extremely capable of handling the outback's formed roads without feeling that it is being stretched or tested. But check the contract fine print before heading off!

And once home you CAN impress the neighbours by leaving it dust covered for a few days. It is almost de rigueur for a Kluger to flag that it has been to the outback.

Carbiz is leading the industry with an ever-growing fleet of green vehicles both Hybrid and Electric. Being not at fault in a car accident means you are entitled for a replacement car just like yours at no cost to you.

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