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VTEC IS DEAD!
LOL well not yet anyways....
Yes, i know this is off a web-site (one of my favorite to read by the way) here is the link http://www.halfbakery.com/idea/Cam-less_20Engine
or if you just want to read it:

\\QUOTE
OK, please be nice to me this is my first post. I’m sure someone out in the world has done this, but I couldn’t find it (High performance cars maybe? Big diesel engines?)
The idea here is to use electronic linear actuators (electronic motors that move in a straight line, not round and round) to open and close the valves. The motors would be computer controlled based on the gas pedal position, whether or not the car is towing something, stop and go traffic vs. freeway, some stupid nut with a 454 parks next to you at a red light and wants to race, etc. I believe this would also reduce emissions and dramatically lower the fuel usage.

Another way to do this would be to use hydraulic actuators on the push rods. This would allow everything to be tucked neatly into the block to minimize the “under-hood clutter.” I hate under-hood clutter.


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Katt, Sep 14 2003
 

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Electro-Magnetic Switches would work for that. but it would be very expensive to make. and lots of electronics. would be a great idea though...
 

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This is kinda weird, because my dad said he thought about this some years ago, but he didn't have the time or knowledge to make it happen. I think ultimately, this will find a place in the modern engine. there are lots of friction losses in a cam setup, and being able to control the valve's behavior is ideal. Heck, you can even get rid of the throttle body like BMW is doing now. What would be really cool is that it would be possible to make custom tunes and you can upload a wild agressive valve timing for the track, and then put it back to stock (or whatever) when you feel the need. Decide to go FI? No problem. Change the tune, that is all.

I can see these being electric as opposed to hydraulic, because little by little, manufacturers are trying to get away from hydraulic fluid (like power steering pumps). Plus, pumps suck up horsepower.
 

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cams arnt that exspenisve or hard to swap though
 

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no they aren't, but actuators allow more control over the engine. Plus, there are no cams, cam belts, sprockets, lifters, etc. Less stuff to worry about over time.
 

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Applying this camless engine theory in a real world situation is yet to be done.

I think it would be expensive also, I think we can sit back and wait, I don't think it will be in automobiles any time soon.
 

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This is referred to as electromagnetic valve actuation and its been done by all comers in the auto industry already. It offers the benefits of all different cam profiles with none of the downsides. You can have a cam profile that lets you sip gas at one moment and then burn the tires off the next. Like essveetee says, there are a lot less parts to break and the amount of interia the valve system has to over come is reduced greatly, allowing much faster system response times. The "cam" profile that would be simulated in a system like this can vary based on loading, engine temp, fuel economy strategy, performance goals, and any number of other attributes. It could even be a variable based on the customers goals. You put series of dials in the car and the customer turns them to the level that they desire, say, good low end torque, high mileage, and 70 mph average cruising speed, and the ecu could generate an algorithm that takes these attributes into account and use that as the "cam" profile. You could even use cylinder shutoff technology similar to displacement on demand that would be much more efficient then the clutch systems that are in use now since you wouldn't have to move around all the mechanical bits still. The only downside is that it would take a lot of power to generate these kinds of electromagnetic fields, and research indicates that the valve seats wear prematurely since magnetic force is inversley proportional to field distance, meaning the closer the valve gets to top or bottom, the faster it goes, slamming the valve into the seat. this could be addressed by altering the amperage through the coils as the valve nears the seat, lessening the field and allowing the valve to accelerate more slowly to a stop. The real problem is the amount of power required and the transient response times of the system. To get the kind of force needed to move the valves and keep them closed, cars would have to run 42V systems at least. And we all know that everybody in the industry is dragging their feet on this one. The response time on the system is something that would be a limiting factor. the combination of the interia of the valve and the magnetic field would yield a limit on the speed of the response on the valve. Essentially, unless the mass of the valve or the power of the magnet is increased, the engine can only go "X" rpm. so there are a lot of limitations to this issue. While it is an intruging technolgy whose idea has been around for a long time, and there are running prototypes (lots of ford rangers) the limitations of the technology and research will have to be overcome before it is implemented into the comsumer market.
 

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you would probobly need a very very large alternator and more batteries to start and run the car..... or use a very large capacitor.
 

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Cap probably wouldn't work, it would be a really dangerous discharge with questionable response time since you'd have to build up the charge and use transitors which would need to saturate before discharge.

The correct way to do it is a 42V system, which is, as I said under development but going slowly. Its not a matter of the technology existing, its just getting everyone to agree on standards. This is a big issue that will be addressed at the SAE World Congress in April. There is also the problem of safety. If a repairman sticks his finger in the wrong place when testing for spark, the result isn't a little arc, its a burned finger/ heart stoppage. Not real good for business.
 
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