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Discussion Starter #1 (Edited)
My new turbo VF12 - VJ11 hybrid (pics inside - 56k not today)

Well I have been talking about it for ages and now I have it ready to install tomorrow.

OK for starters a VF12 is a RHB52 found on the 2.0 Lt Liberty RS.

Here is the Compressor. 45mm minor / 56mm major. Yes WAY bigger than a T-bird compressor.




NIICCE! Notice the curved blades, this is how to identify the largest RHB5 turbos.

Now the turbine. 46.5 minor / 52.5mm major and 10 blades versus the VJ11's 9 blades.




If right about now you are saying "what the that wont fit a VJ11 turbine housing" you are right, read on to see what needs to ge done.
 

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Discussion Starter #2 (Edited)
Ok the first thing you need to do is find someone to machine your VJ11 turbine housing to fit the VF12 turbine.

For me that was easy as I am one of the design draftees at a mining equipment manufacturer.
So I went to the most senior machinist who is a decent guy with the VF12 turbine housing and a spare VJ11 housing to see what he could do.

There are two areas of concern, obviously the bore of the turbine housing needs to be increased which you could even do with just a hone.
But there is another area to modify as shown here. Sorry about the orientation, for some reason I couldn't rotate the pics with IMAGESHACK.

The bore for the VJ11 turbine sits about 16mm form the back face. This is to clear the blade tips.


Whereas the VF12 turbine bore sits at about 21mm. Larger blade tips on the VF12.


And here is the finished product after a quick wire brushing the morning I picked it up.

See the area where the end of the bore had to be deepened.
 

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Discussion Starter #3 (Edited)
Ok onto the compressor side, this bit is a little easier as you all know you just use the matching compressor housing. Shown here along with the intake elbow to suit the Subaru Liberty inlet system.



Now that cant be used as is because the elbow can only face 2 ways.
On a MX6 that would be straight into the radiator or back toward the engine.

So I cut the end off the elbow and had it welded onto the housing by the welding supervisor, he didn't have a TIG setup on hand so he MIG welded it with an ARGON sheild gas, as shown here.


Not as pretty as TIG but its not coming off in a hurry!
 

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Discussion Starter #4 (Edited)
Now onto assembling this beast.

For starters you need to use the VF12 centre cartridge. So in the begining you need a complete VF12 turbo.

This is due to the larger compressor. There is a rim on the compressor back plate that the compressor sits in.
Example shown below. (thanks to SixSick6 for the pic, pic shows VJ11 compressor housing and RHC6 compressor wheel AFAIK)
On the VJ11 the diameter of the rim is too small for the VF12 compressor.



The rest of the assembly is the same as rebuilding any RHB5 turbo or hybrid.
 

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Discussion Starter #5
OK so here is a pic of the assembled turbo ready to bolt onto the 6.
Well almost, the VF12 wastegate actuator is too hard to use beacause it has a bent rod versus the straight rod on the VJ11.
So that will have to be assembled once I have the stocker off.


I picked the spare manifold and O2 housing at the same time as I got the spare turbine housing. From some guy who had snapped his turbine shaft.

Before assembly I opened up the wastegate port to hopefully avoid surge.
And here you can also see that I had to dremmel the turbine bore a bit to get the turbine centred.
Unfortunate, but I knew this was a possibility as the machine used to do the machining
is better suited to its usual task
of line boring front end loader attachments that weight upto 1000Kg rather than tiny little turbine housings.



And lastly here is a pic' of the complete manifold, turbo. O2 housing and new heat sheilds that will go on the moment I have the time.

Nice socks EH!

And one 3/4 shot just because I like the photo.
 

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Discussion Starter #6
Comments, questions, flameage, Karma?

You might as well post if you have gotten this far!
 

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Discussion Starter #8 (Edited)
must spread rep
Thanks for trying.

P20 housing both on the VF12 and VJ11 according to the FAQ and the housing markings.

20mm^2/mm of radius. Which in inches equates to about a .79 A/R ratio.

So the A/R is actually quite high but yes the O/ALL size is low, ie, Small entry.
 

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Discussion Starter #10
No offence taken.

The reason is besides newer nissan T3 flange turbos I don't think a second hand T3 would be much better than this.
Or not enough to make the extra effort worth it.

For starters forgive me if I am wrong but the compressor wheel on this is a 64 trim
(45/56)^2*100
It is not that far off in size compared to a T3 60 trim, the T3 has a 60 mm major diameter versus the 56mm of the VF12.
So this in theory should have a little bit more potential than a T3 50 trim.
Very close in inducer size and higher trim.
And almost as much as a T3 60 trim. Not enough difference to wory about since neither will be over worked on an F2.

And the turbine housing size is proven to work on the F2, I just hope that the larger wheel doesn't stuff it up too bad.
At least it has one extra blade to catch the exhaust pulses and the blades are also very curved compared to the stocker.

But probably the biggest factor in why I went this route is that I have only one car available to me now days.
It used to be that if my car was off the road I could borrow my mum, dad, brothers since they had a spare, but they got rid of the spare.

Also I know that I could do almost all of this in my garage except for the machining of the turbine housing and welding on the snout onto the compressor housing.

And I know that I can swap in out in a few hours if all goes smoothly.
All fittings / hoses will fit, all mounts and braces will work.

Going for a T3 my car would have been off the road for at least a couple of days.
Which just doesn't work being the only driver in my house with a wife and child. I need a car every day.
 

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Why didn't you made a exhaust manifold for the VF12? And build a hybrid instead?

(Bakmans has a exhaustmanifold and VF12 ready for my MX-6)
 

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Discussion Starter #13
Why didn't you made a exhaust manifold for the VF12? And build a hybrid instead?
Duh - I did build a hybrid. A VF12 - VJ11 hybrid :shrug:

(Bakmans has a exhaustmanifold and VF12 ready for my MX-6)

So do I.
In effect this hybrid is a VF12 eccept that it bolts to the MX6 manifold.
VF12 wheels, VF12 centre cartridge, VF12 compress cover & MX6 turbine
housing modified to match the VF12 turbine housing.

So why make a manifold again? To spend more money?
 

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Discussion Starter #14
Nice. I have a VF8 that I still havent done anything with. Maybe I'll take it apart and see how close it measures.
Thanks Damian did you ever get your VF39 on one of your cars? Hows it go?
 

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Ya know, I actually have everything for it but I havent put it on. The MX6 was my daily driver for a long time and I couldnt have it down for more than a weekend so all I really did was collect parts to get it done. I have an entire intercooler pipe kit with an EVO VIII intercooler. My F2T exhaust manifold has the VF flange wleded to it and I have all the nuts and bolts as well as an exhaust flange for the VF39 but I'd need to make an elbow to connect it. Thats really the only thing that has been stopping me. In Ca we have emissions done every two years and everything has to be stock. My next test comes up in Aug so I'm thinking of completely finishing the car after that. I bought a DC2 Integra GSR so...the MX6 has been parked.
 

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Discussion Starter #16
Parked! You know that an MX6 is so much nicer to drive than an Integra.

Like how I didn't call the turbo a "high flow" turbo.
 

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Duh - I did build a hybrid. A VF12 - VJ11 hybrid :shrug:

(Bakmans has a exhaustmanifold and VF12 ready for my MX-6)

So do I.
In effect this hybrid is a VF12 eccept that it bolts to the MX6 manifold.
VF12 wheels, VF12 centre cartridge, VF12 compress cover & MX6 turbine
housing modified to match the VF12 turbine housing.

So why make a manifold again? To spend more money?
Aaaah Allright.
then is clear for me why you choose this way for doing it
 

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It'll be intersting to see what difference there is on the road.
 

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Discussion Starter #20
Here is a couple of comparison pictures.
All ready to bolt in, with VJ11 wastgate actuator & water pipes.
Just waiting for the missus to get back with some hose so I can replace the coolant feed & return.

Inlet side of turbo.



And overhead. Again sorry about the orientaion.

 
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