Variable Valve Timing

[Cup ov Ste 53]

Is it a phase shift on the inlet cam . (the position of the camshaft alters in relation to the pulley, its not fixed)
If thats right what actuates the shift ? C F force ? If thats the case then is it a gradual shift? the faster the engine runs the more the advance ? (to a fixed point)

Or is it something completly different ? Excuse my ignorance, Im just new to these clios and havnt worked on, or had anything to do with one before.
:S

 

[boulterboy]

http://en.wikipedia.org/wiki/Variable_valve_timing

 

[BenR]

Phase shifter yes.

straight single 16 deg advance on inlet only, static ex.

Phaser traditional vane type using oil pressure through centre of camshaft.

Activated by parameters ^1450rpm and ^800mb.

Its crude and basically to reduce overlap to nill for smooth idle and emissions, economy. Has no real bearing on power production.

 

[edde]

Thee Clio vvt isn't like Honda etc
Its actived at 1.6k and deactivates at 6k from memory so long as certain conditions are met ie 750mbar intape pressure (ie high throttle) and when coolent temp is over 60 degrees or something.

All it does is advance the intake cam timing by 16 degrees. it operates from a phase shifter and oil pressure ie oil gets pushed in and moives the cam.
Pm me your email address and i'll send you a file about it.

 

[BenR]

you'll be surprised how little 800mb is throttle wise when running speed density eddy.

 

[edde]

you'll be surprised how little 800mb is throttle wise when running speed density eddy.

I love it when you go all geeky talk Ben.
Any idea roughtly how much 800mbar is throttle wise (obviously it depends on rpm etc but just as an idea.

 

[BenR]

as low as 1/4 throttle.