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Old 24th March 2010, 18:04   #16
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@aargie
desmo valve system, operates with solenoids: as in electronic signal actuates the valves. this eliminates heavy cams-components,(considerable weights! in lightweight engines..)
plus, gives flexibility to have variable timing

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Originally Posted by driverace View Post
@aargie
desmo valve system, operates with solenoids: as in electronic signal actuates the valves. this eliminates heavy cams-components,(considerable weights! in lightweight engines..)
plus, gives flexibility to have variable timing
and lift, at any/all rpms, of all individual valve sets, independant of others!

I think, that is the dividing line.

@one-out-of-multiple cylinders firing at idle, umm, I remember reading this, that in V12, in some eco mode, only 4pots fire, while the others dont!
(sorry, I do not recall the source, though)

My thinking on the matter is, that if we keep the inlet nad exhaust valves of non-powering cylinders open in the case suggested by you, we can have the least possible resistance from the non-powering cylinders.

If we are missing/overlooking some things here, experts, please shed some light!

Care.

Ace.

Last edited by Rehaan : 26th March 2010 at 14:35. Reason: Merged on request. FYI - its okay if you make consecutive posts >20mins apart :)
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Old 26th March 2010, 10:06   #17
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Quote:
Originally Posted by driverace View Post
@aargie
desmo valve system, operates with solenoids: as in electronic signal actuates the valves. this eliminates heavy cams-components,(considerable weights! in lightweight engines..)
plus, gives flexibility to have variable timing
I do not think Desmo operates with solenoids. It uses an extra rocker arm to push the valve close rather than a spring. It seems the springs can lag at high speeds and the valve can remain partially open even when the piston is at TDC.
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Old 26th March 2010, 11:01   #18
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Quote:
Originally Posted by PhiGolden View Post
I do not think Desmo operates with solenoids. It uses an extra rocker arm to push the valve close rather than a spring.
Strongly agree with you Golden;
@driverace - Here's my source to show you buddy - Desmo Valve Animation
PS - My handle is aargee & not aargie
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Old 26th March 2010, 16:44   #19
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Wow, desmo valve system is neat. No need to worry about spring rating, valve float etc. The bottom arm will make sure the valve returns back on time.

But are those rocker arms adjustable to cams with higher lift or vvt cams?

Shan2nu

Last edited by Shan2nu : 26th March 2010 at 16:48.
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Old 31st March 2010, 11:29   #20
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Quote:
Originally Posted by PhiGolden View Post
I do not think Desmo operates with solenoids. It uses an extra rocker arm to push the valve close rather than a spring. It seems the springs can lag at high speeds and the valve can remain partially open even when the piston is at TDC.
Yes, I actually read about those more later.
I was confusing them with this
Name:  rsc_camless1.jpg
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source:
::: Automotive Control Lab :::
replacing the Hydraulic system with electrically actuated one (electro-magnetic in nature)

Quote:
Originally Posted by aargee View Post
Strongly agree with you Golden;
@driverace - Here's my source to show you buddy - Desmo Valve Animation
thank you for the animation!
My Bad.
Quote:
PS - My handle is aargee & not aargie
Sorry aargee ~ !
Do Have a look at what I was talking about. (wrongly referring it to as desmo valves)
Camless Engines Promise Greater Efficency - Fuel Economy - Jalopnik

Doing the 6S engine on desmos seems tough too!


Quote:
Originally Posted by Shan2nu View Post
Wow, desmo valve system is neat. No need to worry about spring rating, valve float etc. The bottom arm will make sure the valve returns back on time.

But are those rocker arms adjustable to cams with higher lift or vvt cams?

Shan2nu
We wll not need to worry about any cam profile/ or no need to change the cam profile for low/high speed gains !
the solenoids can be adjusted with simple programs to do so.

perhaps we can assign some non-linear relation with rpms for the lift & duration of the lift.

Sorry for the goof-up.

Care.

Ace.
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