Variable vein turbo, how does it work?

[yARIC008]

Does anyone know how the variable vein turbo works? From what i gather it is controled by hydraulic pressure lines. Is this true. If so, what are the specifications. What in the turbo is actually moving and changing, how is it actuated inside?

 

[Cowboy_Customs]

Im assuming your refering to the Variable Geometry turbo, thats factory on the 6.0's and D-max's. Its acctually partially controlled by the puter. The way it works is there are veins in the turbo that open and close, to provide sufficient boost, and much quicker spool up. The compter uses the sensors to determine weather or not the veins should be open or closed, I'll do some research, there was actually a Tech piece on this on the show "Extreme 4x4" on Spike TV a while back. I'll go see if I can get a link to better explain it for ya!

:draw

 

[Cowboy_Customs]

OK here ya go.

http://www.bankspower.com/sidewinder-turbochargers.cfm

its not much, but it helps a little.

 

[JohnBoyToo]

I was always under the impression that the turbo vanes didn't change, but the vanes over the inlet would open and close - somewhat akin to your window blinds to keep the air speed at optimum....

but maybe I don't know anything either

 

[yARIC008]

Okay, well i'm still not very clear on this.

I understand that in a 6L it has all these sensors and computer commands to tell the turbo what to do, but i'm not interested in that. I'm interested in how the turbo physically is changing the flow of air inside ofit. On that banks link it says it changes the exhaust flow but i don't really understand how.
When the 6L computer commands the turbo to do something, what is the computer actually telling what to do, is it a hydralic pressure regulator?


But, say i have a variable geometery turbo sitting on a table, what actually needs to change for it to be variable? Is there a hydralic pressure line that runs to it and variable pressures change whatever changes the vanes inside of it? I'm pondering how i can use one of these turbos for a project of mine.

I'm thinking i'd basically need the turbo, a hydraulic pump, and some sort of hydraulic regulator to control pressure going to the turbo. But i need to know the pressures and all that mess. So anyone know? Am i right in thinking that's all i basically need?

 

[budtoh3zo]

Its controled by hydrolic pressure, The vains are on the Ex side so it works like a waste gate when its closed then its bypassing some of it around the turbine, I will see if i can find it again

 

[Ak HDM]

The vgt uses engine oil pressure to move a piston to change the angle of the vanes in the exhaust side controlling the amount of exhaust that goes through the turbine,thereby controlling the speed of the turbo & the amount of boost. The Pcm sends a signal to the solenoid valve on the turbo,to regulate the position of the vanes. The oil is supplied by the lube line for the turbo. All the mechanism is in the center section of the turbo.
I hope this helps
Mike

 

[yARIC008]

Interesting. So the valve that moves the vanes, what kind of signal does it get from the PCM, it's a variable type thing, not an ON-OFF type thing, right?

What kind of pressure is on the oil line from the engine? Is the oil just under pressure from the oil pump, like.. 20-50 psi, just like normal engine oil the gallery?

Basically i just need like a tech specs. sheet for the 6L turbo.

 

[Ak HDM]

I don't have a spec sheet on the turbo, maybe if a tech reads this thread they can come up with one. I'm not sure about the signal to the valve, but I would guess that it would be pulse width modulated. The oil pressure will be whatever the lube system pressure is.

 

[Ak HDM]

Also check out 6.0 psd bible in the tech articles section it explains the workings of the turbo.

 

[tbirdfiend281]

the VGT signal in the pcm is a percentage piece. all the pcm will do is command the piston, located in the middle of the turbo, to change the vane size and pitch. i will ahve to find a way to get some pictures of the ford book that decribes how the VGT vanes work, it has a cutaway picture of the turbo, so there may be one floating around the internet. the oil supply line works off base engine oil pressure so ya like 20-50psi.

when the vanes change pitched it also effectly increases or decreases the surface are of the turbo, not the actual boost it is making. its like having a twin turbo setup with a small turbo for low rpm spooling, and a big one for high rpm spooling, but in one turbo, and is around to eliminate turbo lag that is "expierenced" in the wastegated 7.3L PS system. (i dont think 7.3s have lag at all really IMHO though)

 

[tbirdfiend281]

straight from ford itself

"The minimum engine oil pressure specifications are 82.7 kPa (12 psi) at 700 rpm, 165.5 kPa (24 psi) at 1,200 rpm and 310.3 kPa (45 psi) at 1,800 rpm with the engine at operating temperature.
"

 

[icanfixall]

Looks really neat. That exhaust manifold interests me a lot. I'll bet I could make something like that so we in the IDI motors could run a PSD turbo detuned of course. BTW... Did anybody notice the "experimental" Fleatgard oil filter that says DO NOT DESTROY printed on it..... Wonder what they have going on there.....

 

[yARIC008]

I'll bet I could make something like that so we in the IDI motors could run a PSD turbo detuned of course.

Well, that's what my eventual goal is, but I don't have the means to create such a thing at the moment.