Fitting VGT turbo

I'm installing the VGT (variable turbine geometry) turbo from a 110hp k9k to the 80hp k9k. I'll probably have to make custom adaptors for the exhaust manifold.
4PsaO

https://imgur.com/gallery/4PsaO

I have completely removed the turbo and exhaust manifold. I've made templates of the screw pattern and hole size of the exhaust manifold and exhaust input on the turbo. Now I just need to make an adaptor plate to join the two. I will most likely port the exhaust manifold, increasing the diameter and hopefully reducing any restrictions. The original intake side pipes fit so no modifications needed there.
https://imgur.com/gallery/LfmaN

Update: Managed to get some adaptor plates plasma cut out of a 5mm steel plate. The parts were designed in CAD. Two of the parts are adaptor plates which will be used to attached the turbo to the original exhaust manifold without any modifications. The adaptor plates will bolt to the manifold and tirbo, whilst sitting fit flush with the surface by countersinking the wholes. The two plates will then be secured to each other using 3 seperate holes. The smallest part will have a steel tube welded to it and attach to the turbo outlet to the engine. The last part will also have a tube welded to it and used for the exhaust output on the turbo. I will update again once the parts have been sanded and the holes tapped
https://imgur.com/gallery/Mq7nS

Update: Finished the plates and attached the turbo to the manifold. Had to undo engine and gearbox mounts to tilt the engine slightly forward to make enough room for the larger turbo. Thankfully the turbo could have its intake and exhaust housings rotated freely making it easier to find an ideal position for oil feed and drain as well as the wastegate. Oil pipes were made by bending spare solid piping and making them fit. A pipe from the wastegate/VGT actuator is attached to a pipe going to the vacuum pump. I am still experimenting with the the VGT, if possible I would like to control it mechanically. If not, I have sourced the solenoid originally used to regulate the VGT.
https://imgur.com/a/0qIba
 
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Can you tell me how to take the metal pipe off that goes to the EGR? I'd like to clean mine out but cant see how it comes off.

Also what difference will the VGT make to your engine?
 
OP
OP
Sina
There are two 10mm positioned vertically behind the pipe (just before the bend) that hold a bracket in place. Once those are removed, pull the pipe to the left so that both ends are free and then just wriggle it out.

The turbo will obviously increase the HP and torque as it is larger than the original, but the VGT is what makes it interesting. In the exhuast side housing there are vanes that can vary the size of the effective aspect ratio (the largest diameter the air travels through). By reducing the effective aspect ratio, the pressure of the air travelling through decreases but the velocity increases, thus allowing the turbo to spool at much lower RPMs, acting like a smaller turbo, making the increasing in power more usable. Once the engine reaches a certain RPM the fins stop restricting and it acts like a bigger turbo.

You could think of it as a sequential turbo setup in a single turbo.
 
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There are two 10mm positioned vertically behind the pipe (just before the bend) that hold a bracket in place. Once those are removed, pull the pipe to the left so that both ends are free and then just wriggle it out.

The turbo will obviously increase the HP and torque as it is larger than the original, but the VGT is what makes it interesting. In the intake side housing there are little fin that can vary the size of the effective aspect ratio (the largest diameter the air travels through). By reducing the effective aspect ratio, the pressure of the air travelling through decreases but the velocity increases, thus allowing the turbo to spool at much lower RPMs, acting like a smaller turbo, making the increasing in power more usable. Once the engine reaches a certain RPM the fins stop restricting and it acts like a bigger turbo.

You could think of it as a sequential turbo setup in a single turbo.


Thank you very much, I have a new EGR to fit, and would like to clean the pipe first - some people's seem to be chocked solid.
 
OP
OP
Sina
how are you gonna control the vgt sina ?
Hi Frank,
The VGT should be controlled via the vacuum in the wastegate. I'll initially use the vacuum from the vacuum pump and test. If that doesn't work well, I'll use a solenoid controlled by a potentiometer attached to the gas pedal.
 
OP
OP
Sina
the vanes work in a different way to a w/g tho sina, they are controlled by the ecu
good luck tho :)
I agree that the vanes and w/g work in different ways but if you have a look at this diagram
turbo_compresor_geometria_variable.jpg

My turbo operates the other way around, so as the vacuum increases, the vanes become less restrictive. Hope this explains it.
 

frank

Club Member
yes opposite direction, but vnt,s are engine load controlled too tho eh
i fitted a hybrid wastegated turbo to my cdti van and had the same hp as the later vnt cdti, the only advantage of the vnt had less lag/earlier boost
 
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