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Source:AutoBlog

"Honda introduced the wonders of their innovative VTEC (Variable Valve Timing and Lift Electronic Control System) technology to Americans by rolling out the NSX in 1990. At the time, many considered the technology to be the normally-aspirated alternative to turbocharging and supercharging. For some, though, Honda engineers made the turbos and superchargers seem like archaic add-ons because instead of increasing horsepower by dumping more fuel into the combustion chamber with high air pressures, the brilliance of VTEC actually looked to improve the engine's combustion efficiency as you approach redline. The result was a horsepower punch with a limited hit on fuel economy.

Since then, there have been a few different iterations of the technology. In 1992, Honda focused their efforts on gas mileage and introduced VTEC-E which increased efficiency by using a sliding pin that kept one intake valve per cylinder closed at lower RPMs. In 2002, the i-VTEC arrived to U.S. shores which added camshaft phasing for either higher performance or increased fuel efficiency depending on which model vehicle it resided in.

Today, Honda announced the latest iteration of its VTEC technology (simply dubbed Advanced VTEC) which they plan to release into production within 3 years. The system offers increased control over intake valve lift and phase under different driving conditions. Preliminary internal tests show a significant increase in torque throughout the rev range as well as a 13 percent improvement in fuel economy. And being a Honda, you can expect the new engines will run relatively clean. The company states that they will meet U.S. Environmental Protection Agency LEV2-ULEV standards."

[Source: Honda Motor Company]
 

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Today, Honda announced the latest iteration of its VTEC technology (simply dubbed Advanced VTEC)... Preliminary internal tests show a significant increase in torque throughout the rev range as well as...
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That has been the main weakness of their current V-TEC technology is torque. That should be a strong system once it hits production. Leave it to Honda! :yesnod:
 

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that's what I like about honda.....Not everybody likes a Turbo Add on to their Vehicle, so Honda pushes the envelope and Develops their NA Engine and Still manages to spank any other Car on the road that is Turbo charged.

Why can't mazda do this instead of taking the easy way out and Just slapping a Turbo on an Engine that can't handle it past 18 psi?
 

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So Honda's finally doing something about their crappy low end performance, big deal.
 

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So Honda's finally doing something about their crappy low end performance, big deal.
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I wouldn't exactly say that honda's 6-cylinders have crappy low-end performance. Particularly since I own a crappy low-end performance 6S :) The fours...well, that's a different story.
 

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So Honda's finally doing something about their crappy low end performance, big deal.
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I wouldn't consider it crappy, but the chief complaint is the lack of low-end torque (one of the reasons why I didn't get a TSX), and the power being too high in the rev range for normal stop-and-go driving.

I'd love to see how it performs when it debuts. Sounds promising...
 

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I wouldn't exactly say that honda's 6-cylinders have crappy low-end performance. Particularly since I own a crappy low-end performance 6S :) The fours...well, that's a different story.
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Well yeah, you're right, I was a little vague.
 

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Honda's current VTEC has great low-end when they want it to. Look at the TSX. [Dyno]

Really, Honda's current system (used in their better engines) is flexible enough to do whatever they want. They can vary cam phasing, lift, and duration. There's really nothing else to vary. All a new VTEC system can do is increase the granularity between these changes; in other words you won't feel a kick when the bigger cam lobes kick in.

Now, what I think Honda could improve is their execution of their technology. Their hardware is fantastic but I think it has more potential than what they're using it for. Honda could use VTEC to build an engine that switches to an atkinson-cycle [link, Wikipedia] when at part throttle. In the case of a turbo engine, they could use VTEC to create a variable-displacement and variable-compression Miller-cycle engine. Now that would be something!
 

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The next logical step would be to have variable lobe profiles instead of the current 2-profile system. This would probably be accomplished by grinding the varied profile onto the cam and then physically moving the cam back and forth as opposed to merely engaging secondary cam lobes. This is just a guess on my part, but I would think that this is the net logical progression of the system.
 

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http://www.autoweek.com/apps/pbcs.dll/arti.../FREE/510140701

Valeo tests camless system for gas engines; supplier hopes to produce fuel-saving technology by '08

How it works

In all automobile engines, the crankshaft is connected to the camshaft with a belt, chain or gears. As the crankshaft spins, it turns the camshaft, which in turn opens the intake and exhaust valves in sequence. Much of the energy produced by the engine is lost because the crankshaft has to spin the camshaft.

In a camless engine, the valves are opened and closed electronically.

The advantages are numerous:

* Internal friction is reduced greatly because there are fewer moving parts. At low speeds, about 25 percent of an engine's friction is caused by the valvetrain.

* Horsepower, torque and fuel economy are improved because the crankshaft's power is driving only the wheels.

* Emissions are reduced because the computer-controlled valve timing is infinitely variable. Each valve in each cylinder can be opened and closed independently, something not possible with a traditional engine.



Valeo's system uses electromagnetic actuators to open and close the valves. The actuators are placed on top of each valve under the valve cover.
 
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