What is VVT-i ( if u curious about VVT-i in prevous post)
VVT-i
From Wikipedia, the free encyclopedia.
VVT-i, or Variable Valve Timing with Intelligence, is an automobile variable valve timing technology developed by Toyota. The latest version of VVT-i varies the timing of the intake valves by adjusting the timing chain connecting the intake and exhaust camshafts. A pump applies hydraulic pressure to adjust the gear driving the timing chain.
Toyota recently started offering a new technology, VVTL-i, which can alter valve lift (and duration) as well as valve timing. This is accomplished differently than Honda's VTEC. Instead of switching between two different cam shafts, there are spacers that are slid between a single cam shaft and the valves. At higher RPM, controlled by the ECU, oil pressure is directed to push the spacers between the camshaft lobes and valves, effectively simulating a much "hotter cam" and creating increased valve lift. When the engine falls in RPM the spacers are pulled out of action and the engine operates more economically. This system is used in the Yamaha designed 1.8 liter 4 cylinder 2ZZ-GE which is used in the Toyota Celica GT-S, Toyota Corolla XRS and Lotus Elise 111R. This variable lift technology allows the engine to be quite fuel efficient at lower RPMs and, when called upon, able to produce much more power at the expense of fuel economy.
For 2006, the company will add dual VVT-i, which varies timing independently on both the intake and exhaust cams. This will debut on the 2006 Toyota Avalon's 2GR-FE V6.
From Wikipedia, the free encyclopedia.
VVT-i, or Variable Valve Timing with Intelligence, is an automobile variable valve timing technology developed by Toyota. The latest version of VVT-i varies the timing of the intake valves by adjusting the timing chain connecting the intake and exhaust camshafts. A pump applies hydraulic pressure to adjust the gear driving the timing chain.
Toyota recently started offering a new technology, VVTL-i, which can alter valve lift (and duration) as well as valve timing. This is accomplished differently than Honda's VTEC. Instead of switching between two different cam shafts, there are spacers that are slid between a single cam shaft and the valves. At higher RPM, controlled by the ECU, oil pressure is directed to push the spacers between the camshaft lobes and valves, effectively simulating a much "hotter cam" and creating increased valve lift. When the engine falls in RPM the spacers are pulled out of action and the engine operates more economically. This system is used in the Yamaha designed 1.8 liter 4 cylinder 2ZZ-GE which is used in the Toyota Celica GT-S, Toyota Corolla XRS and Lotus Elise 111R. This variable lift technology allows the engine to be quite fuel efficient at lower RPMs and, when called upon, able to produce much more power at the expense of fuel economy.
For 2006, the company will add dual VVT-i, which varies timing independently on both the intake and exhaust cams. This will debut on the 2006 Toyota Avalon's 2GR-FE V6.
Comments