I'm not sure how much you guys know about the intimate workings of 4-strokes valve-trains, but here's my question...

I read somewhere that most crotch-rockets make little power down low mostly because their valve-train is set to make good power above like 8 or 10k RPM...(they have very high valve-lift/ timing that is only efficient at high RPM but useless down low)
Now I know about VANOS and V-TECH and such, but mechanized camshafts can only do so much. I know I'm going out on a limb here, and probably way out of your field as well, but would it be possible to do away with the camshaft all together and move the valves with a system similar to Evinrude's new E-TECH.....


...E-TECH:...Where the fuel-injector-'pistons' are moved foward AND back by a celonoid or whatever...(vs. Fitch's spring-return system) Evinrude claims this allows for higher RPM because the celonoid is faster than the spring.

So could a computer manage all 24 valves in say... a V6, if they were controlled by individual celonoid actuators that moved the valves up and down...1 for each valve. In other words you would be able to open both exhaust valves and only one intake for highway driving or economy. And when you pushed the go-pedal into the carpet the engine would open both exhaust and both intake valves at exactly the right time, duration, and lift to make MAX power at ANY paticular RPM. (low lift for low RPM, High lift when RPM is high) Without any steps; just smooth transition. (forget that "stepless valve timing" stuff; I'm talking about somthing totally new.)

While some engines have valve-trains set for economy, and others for low-end power, and still others for high-end power...This could be ALL 3...and everywhere in between.

Is what I'm talking about not practical? Or is it something worth a little research? Whatever you guys can tell me will be much appreciated! Humor me with specifics and tech stuff, Please.

 

I'm nit picky, so it's spelled VTEC and solenoid.

This system is possible, and i believe Mercedes has done things with it on it's Formula One engines. The problem is getting the solenoids to react fast enough, bringing down the cost, and longevity. Also, for the most part, this is not a fail-safe system in that if one of the solenoids get stuck open, you have a problem.

It's a system that deserves research, and I think Audi is looking at it too. It will become a little more practical when 48v systems become the standard in cars, as the 12v systems draw a lot of current.

I'd be interested to see what anyone else has found on this subject. You are right on the benifits, an infinite number of cam profiles for every possible condition, and you could easily shut down cylinders to aid fuel economy under light load conditions.

 

This is not a new idea and a LOT of people are currently looking into it. I think they might have already done it in a diesel application, but I'm not sure. There are problems with this, however. For one, the solenoids need to be very large, powerful and heavy...to the point that a lot of their benefits might be offset. Another difficulty I heard mentioned is that a benefit of cams is that by design they slow down the valve so that it doesn't slam into its seat. This would be hard to accomplish in an electric solenoid....

But yeah, the actual idea is very good and if someone pulled it off they could make a hell of a motor.

 

BMW is real close to selonoid controlled valves... but at the same time they are looking for optimal fuel efficiency as well as performance.... its gonna snag a nice price tag as well as massive computer related problems...

 

F1 has been doing this

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Lsos &raquo;</TD></TR><TR><TD CLASS="quote">slow down the valve so that it doesn't slam into its seat</TD></TR></TABLE>

I forgot about that one too, thanks for pointing that out.