VVT-i or VTEC what's the difference??

Indonesia's new car lot with the engine drive system valve, VVT-i, VTEC, valvetronik or vanos. Toyota generally named mesinya VVT-I. While named the Honda VTEC. VVT-i VVT-i system (Variable Valve Timing - intelligent) is a series of devices to control the camshaft drive. Its purpose is to adjust the valve opening time with the machine. So they can get optimum torque at each speed level. At the same time save fuel and reduce exhaust emissions. At the Toyota engine, this system was applied to the intake valve. Exposure time of the camshaft can be varied in the range of 60 degrees. For example, at the start, a cold engine and stationary engine without the expense, timing pushed back by 30 degrees. This method will eliminate overlap. That incident came in and exhaust valves open simultaneously in exile since the end of step a new intake valve will open some time after the exhaust valve fully closes. Logically, in this condition do not have to work extra engine. With the closing of the exhaust valve, no fuel is wasted when sucked into the engine. Consumption of fuel to the engine more efficient and friendly lingkungan.Sedangkan when there is load, the timing will be advanced 30 degrees. The degree of overlapping will increase. The goal is to help push the exhaust gas heat plus a mixture of fuel and air intake. In addition, the time compression also increases because the intake valve closes too early. The effect, so better volumetric efficiency. To make it happen, there is VVT-i controller on the intake camshaft timing gear. This tool consists of housing (house), then in it there is room to move the vane oil (the propeller). Propellers are connected with the camshaft. Inside are two oil lines to each room in the house oil VVT-i controller. From this point a different oil, vane valve will regulate the exposure time. Advanced timing advance positions obtained by filling the oil into the back room of each blade vane. So that the vane will move forward and position timing too advanced 30 degrees. Own the oil pressure provided by the Oil Control Valve camshaft timing is governed by the engine ECU. In contrast, for the retard (backwards), the space in front of the vane will be filled and the position of timing back. Meanwhile, if required at standard conditions, there is a pin that will lock the fixed vane position is in the middle. Actually there are more sophisticated system, called VVTL-i (Variable Valve Timing Lift-Intelligent). Besides playing time of valve opening, high, too differentiated. Advanced technology VTEC Variable Valve Timing and Lift Electronic Controlled (VTEC) Honda innovation results show a different mechanism. The main difference is the inclusion of valve movement. In the 16 valve engine, there are respectively two incoming and exhaust valves in each cylinder. VTEC is applied only on the intake valve. In this valve controlling engine efficiency is more influential. The assumption was that the process does not require the disposal of the variable valve opening because more smoothly exhaust, engine work will be more lightly. In VTEC engine, the second intake valve does not always move together. For example, at low speed there is only one valve is open. Opening is relatively small because the characters are punched camshaft valve is suitable for low round. This condition is considered fit for the machine. Because of the low rounds do not need a lot of air supply. In addition, there could be air turbulence to help mix the fuel. Machine so economical, efficient, environmentally friendly too. As the rise in engine rpm, air supply needs are also increasing. Directly answered by the second valve. Larger opening for nok chamshaft have character degrees higher. Fun, the first valve was then opened wider. This is because there are pins that connect the rocker arm and push pin. Automatic pin was going to lock the second rocker arm. Because the second rocker arm is driven by the duration of peak camshaft is higher, so follow the movement of the first valve. In addition there are also VTEC i-VTEC (intelligent VTEC), which also features forward and rewind mechanism of ignition. Certainly the results more leverage to improve engine efficiency.

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