Electronic Camshaft

[bangbangskeetskeet]

I was just informed a couple days ago that on the new 370Z they have rockers that do basically the same thing Tyler. The example I was given was depending on engine speed the rocker arms will move 2 different distances, say just for example 2mm and 10mm. So at low rpm crusing they will move 2mm using less fuel and less power but immediately once more throttle is added they will open the 10mm and let in much more fuel and air to bring power up. Now I don't thing the cam phases up and down just the rockers move more or less depending on throttle.

[Frenchy]

In theory you could do the same thing with lifters, actually it has been done. Rhoads lifters. Only they do it without electronics. They work like male genitalia, the more they work the harder they get. That's the easiest way to explain it.

[jetersaurous]

the way that i understood it was that the whole camshaft itself will be removed. it sounds to me like they are gonna put an electronically controlled lifter type doohickey on each valve. just how i interpreted it

[txarkitekt]

So what you are saying is instead of controlling it with a chain, control it electronically and move it up and down? Still sounds like V-TAK to me

No Chrissy, I am talking about the cam being mechanically moved. Keep your attempts to foil me coming.

But then again, an adjustable chain probably wouldn't be a good thing. Too much slack might cause it to be thrown off...

In theory you could do the same thing with lifters, actually it has been done. Rhoads lifters. Only they do it without electronics. They work like male genitalia, the more they work the harder they get. That's the easiest way to explain it.

Ah, good find, my light skinned Canadian friend. Same thought as the actual cam being phased, but the thought has been moved upwards to the lifters.

Travis, I did some basic spying on Nissan's CVTC/VVEL technology. It seems as that this has been around for a while. There have been several examples of this variable cam phasing technology. Most of the premier engine builders have divulged into this, carrying their own acronym nomenclature. From what I have found, these are the different types of existing variable valve systems:

Original type of Variable Valve Timing Technology:
- Nissan VTC/CVTC/EVTC
- BMW VANOS
- Toyota VVT-i
- Porsche Variocam

These systems work like adjustable cam sprockets (even better idea than mine ), which allow advancement or retardation of camshaft timing/phasing and subsquently the valve timing/phasing. There's the ability to alter settings in real-time and via infinite steps over a set range. Valve lift cannot be altered with these systems, just cam timing/phasing.


Second Type:
- Honda VTEC
- Toyota VVTL-i
- Nissan VVL
- Mitsubishi MIVEC

These systems have the ability to switch between two (three in the case of MIVEC) cam profiles that are optimzed for different conditions. It is therefore possible to alter between discrete sets of valve lift and timing/phasing that are built into each of the available cams profiles. Discrete means the settings are not infinitely variable, just variable at set profiles ground into the cam.

Third Type:
- Honda i-VTEC
- Porsche Variocam Plus
This system is litterally the combination of Type 1 and Type 2 systems. Valve timing/phasing is infinitely variable, while valve lift remains one of the two fixed settings, as of the Type 2 system.


Fourth Type:
- Nissan VVEL
- BMW Valvetronic

These systems have continuous variable control over valve lift (from a mere crack to full stroke open), making standard butterfly throttlebody a virtual obsolescence. When coupled with their respective Type 1 systems, they also gain continuous variable valve timing/phasing capability. These are the next generation control systems with 100% control over valve activities. Aftermarket camshafts will be all but unecessary because virtually any cam profile can be replicated via simple alteration of two ECU tables.

As you notice, only the intake valves are being phased. Since the exhaust cam design can be a set at max parameters to accommodate the intake's lift and duration, there is no need to phase this side of the combustion process. Variable valve systems are solely for the main ingredient of combustion: air. Not only does this create power on demand and reduce fuel consumption, but it reduces emissions as well.

GM as furthermore taken this application and actually integrated this process into the exhaust side of things. It doesn't matter the engine type (OHC or OHV), GM has been able to vary the intake lift by 40* and the exhaust lift by 50*.

Oh well, I thought it was a neat concept at the moment.