How about that VVT

[Don®]

Do you guys have the same engine code?

[v84lnch]

Do you guys have the same engine code?

iirc, adam has a AWD block, but we both have the LP/HS ecu.

[Dizzy]

091 is the one.  The last block has a correction factor. 

[v84lnch]

091 is the one.  The last block has a correction factor. 

so what have you figures out with block 091?

[Dizzy]

Nothing yet, that's why I'm asking for results from others.  Still waiting. 

[6cylindakilla]

I don't know how much help this will be, but I have access to VAG tech articles for the cam adjusters and VCT for both the 24V VR6 and the 5V motors.  The 5V article was taken from a 4.2L 40V V8 which uses the same cam adjuster principles, but the intake valves are actuated by rockers as opposed to directly by cam lobes.

5V Cam Adjuster:


24V VR6 Valvetrain Operation:


24V VR6 VVT:


Hopefully this is somewhat helpful.

- Dave.

[Dizzy]

Good info, but not sure it helps with the info I'm looking for.   Just so everyone is on the same page, we're looking at what VCT does in terms of performance in actual operation in above idle rpms. 

[VariantStg3]

Aren't we talking about using the selinoid to do what an "adjustable cam sprocket" would accomplish, or is the benefit of the selinoid being able to adjust only the intake cams timing to create the overlap? ...and the true benefit would be to be able to turn it on and off at a specific rpm or boost rate?

[6cylindakilla]

Good info, but not sure it helps with the info I'm looking for.   Just so everyone is on the same page, we're looking at what VCT does in terms of performance in actual operation in above idle rpms. 

Yeah, I know what page you're on.  I was just thinking that it migth be helpful to those who may not have a thorough understading of how the system works.

- Dave.

[bobqzzi]

I don't know how much help this will be, but I have access to VAG tech articles for the cam adjusters and VCT for both the 24V VR6 and the 5V motors.  The 5V article was taken from a 4.2L 40V V8 which uses the same cam adjuster principles, but the intake valves are actuated by rockers as opposed to directly by cam lobes.

5V Cam Adjuster:


24V VR6 Valvetrain Operation:


24V VR6 VVT:


Hopefully this is somewhat helpful.

- Dave.

Hey Dave,

Thanks for posting this!  Very informative.  When you click on the third pic, it pops up the second pic- be great if you could fix that.   

Any and all info you cna post on any subject VW/Audi is greatly appreciated.  The entire object of this forum is to gather and exchange information!

[6cylindakilla]

Fixed.   

If you are looking for anything else VAG techey related, let me know...

- Dave.

[VWtuner-NL]

Hello,

I`m Martijn from the Netherlands and I`m new to this forum.
This thread is very interesting because I also thought that there must be some gain in the lower RPM or less lag.
I have a VW MK1 with a 1.8 20vTurbo engine(AEB) with Schrick cams and a GT30R and installed all the VVT parts to get it tested.
I hooked up the VVT once when the car was smooth idling and when the VVT goes on,
then it runs like you have installed 300 degrees camshafts. It runs very agressive and unregular.
But when I tried to rev it up it goes lean, so the Fuel and Ignition map has to be changed.

Has anyone ever tried it before?
because if somebody already tried it and it doesn`t work then I don`t have to spend time to try and make it work.

Martijn.

[bobqzzi]

Hello, and welcome to the forum.  I don't believe it will be of mush help at all, adn I do question the longevity of the parts if they are cycled continuously.

I am curious, what are the specs on the Schrick cams?  I assume you didn;t bend any valves when you activated the VVT- I am curious just how big a cam you can use without the piston hitting the valve.

[rracerguy717]

Good info, but not sure it helps with the info I'm looking for.   Just so everyone is on the same page, we're looking at what VCT does in terms of performance in actual operation in above idle rpms. 

What it does is increase the over lap , if i remember correctly by 17 degrees this makes the engine run super rich at  cold start up and then the secondary air injection  blows  air in the cylinder   helping heat up the C.C. faster and lowers  cold start emissions  by 2 /3. With this happening helps the cat get up to temp twice as fast also.

 I think  that if you try to rev the motor past 3K when its activated it had some type of saftey not allowing to rev past that point . Dont hold me to the numbers but this is basically how things work it was designed all for emissions but im sure it could be used for performance with a re-design for longer use like Bob mentioned .
  fueling and tuning for the overlap change would be the big problem imo. Maybe with Standelone its possible with a seperate map when activated almost like a launch control feature but at the top of the rpm range  .I read this info many years ago so im trying to pull it out of my head/ hardrive  funny thing is i have a hard time remembering what i had for dinner last night LOL

 just my 2 cents  Bob.G

[VWtuner-NL]

Hello, and welcome to the forum.  I don't believe it will be of mush help at all, adn I do question the longevity of the parts if they are cycled continuously.

I am curious, what are the specs on the Schrick cams?  I assume you didn;t bend any valves when you activated the VVT- I am curious just how big a cam you can use without the piston hitting the valve.

Hello Bob,

I didn`t bend the valves when I activated the VVT.
The cams that i`m using have the following specs:
Exhaust cam lift 10,4 mm/260 degrees/0,7 mm lift at TDC.
Inlet cam lift 8,2 mm/252 dregees/0,8 mm lift at TDC

When the VVT activates the inlet cam advances from 0,8 to 3,6 mm lift in TDC.
I don`t know the valve to piston clearance anymore, But it was close. (less then 1 mm)
(I measured it a few months ago, so i`m not 100% sure on the numbers)

I understand your opinion about the longvity of the system,
But the chain is always "stretched" with oil pressure even on the non VVT systems.
And there is always a bend in the lower have of the chain, only when the VVT is active some more, so I think that the wear on the chainguard is not that much more.

P.S. I have to correct my first post, because yesterday I activated the VVT again and then it`s running indeed very rich instead of lean.

Martijn.