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Here is a project I have been working on since June 2007....time flies when you havent got any!

I have read posts from both Ryan and MattyP and decided that the VF34 was a good turbo to fit, it was about the right size for the sort of power I was looking for....
I also liked the fact that being another IHI product its got the same size round hole as the original, making the adapter plate a bit easy to make...I have made adapter plates for the T25, but its a bit annoying to match the rectangular T25 flange to the round Mazda turbo outlet....
Anyway enough about why I chose it...here is how I went about it.

First I needed a template of the adapter plate I needed.

I cut a plastic template of both the manifold outlet and the turbo inlet, I overlayed both centred around the round centre hole with the orientation I needed

otherside


I cut out an adapter plate from 1/2 inch steel plate using nothing more than a hacksaw and a drill press...

Took a few hours, but I had some time to burn....here is the end result


When I tried to remove the studs out of the manifold, all but one snapped off, as a result I drilled out the studs and retapped the holes to 10mmx1.5
This took much more time than making the adapter plate.
I am using countersunk bolts to ensure a flat mating surface.

I had the surfaces on the manifold machined as neither surface was even close to flat


I then used a single layer stainless steel gasket from a GC FE turbo between the adapter plate and manifold....holes didnt even require re drilling for the larger bolts, I would normally use an annealed copper gasket...but I felt lazy and didnt want to make one up, so we will see how it goes....
Here is the manifold with the adapter plate fitted

and gasket


and now turbo



I read up one some post from sicksix about "re clocking" the turbo, this needs to be done to make sure that the oil drain is at the bottom and the compressor outlet ends up roughly where the factory one does.

One thing I didnt realise, I needed to re locate the wastegate acutator..



I made a paper template of where it needed to fit and then drilled the holes! Its only got two screws holding it on instead of three, but I think it'll be ok

I intstalled the VJ11 oil inlet nipple...and I will use the factory Vj11 oil drain.

I am yet to decide on the coolant supply fittings, at the moment I have MHI TD05 12mm.1.5 ones...but I dont know if the pipe work will end up in the right spot.....

Coolant plumbing and dump/down pipe coming in part 2
 

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You must spread some Reputation around before giving it to chief tool again.
Very nice work.

The only thing I might have done differently is to counterbore the holes instead of countersinking them.
That way you could have used a standard hex head instead of the c/sink socket heads.
And you would be able to get a bit more torque on them, how did you go torqueing the socket heads?

Other than that very, very nice. Good enough to put into production.
And should suit any Subaru turbo since they all carry the same flange pattern.
 

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Discussion Starter #8
Answers

I used countersunk screws as when you counter bore and use ordinary cap screws, you only leave a few mm of material under the head as the cap heads are not much thinner than the plate.
you need to drill more accurately for countersunks, but that didnt represent an issue...I have used this technique before.

If there was demand i'd consider drawing up a plate and having some laser cut...doing one with a hacksaw is fine...but not half a dozen! also I used 10mm bolts the factory manifold uses M8s...I'd really need to make up another one for M8s to give it a more universal appeal...not that drilling and tapping to M10 is a big deal in my opinion.
When I head off to the laser cutters for my FE3 manfold bits, I'll see if I can do a couple...I dont have a good record for doing anything all that quickly tho.

How much did the VF34 cost? $750 USD...Which was other reason I chose it...I got it for what I thought was a good price...It had the right flow figures and a BB core.
As the car is primarily a road car, I wanted to keep it driveable...shooting for 300HP wasnt necessarily a priority.
 

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Did you stay metric fine to avoid vibration undoing things? Or std pitch? Csk is good, you can torque them more than enough with the right tools.

The VF34 should make your 300hp easily enough anyway (stretching it, but still)

I'd like to find a second hand VF34 for the right price to try as a primary/small turbo on the truck.

Fred.
 

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Discussion Starter #11
Did you stay metric fine to avoid vibration undoing things? Or std pitch? Csk is good, you can torque them more than enough with the right tools.

The VF34 should make your 300hp easily enough anyway (stretching it, but still)

I'd like to find a second hand VF34 for the right price to try as a primary/small turbo on the truck.

Fred.
I used M10x1.5 countersunk on the adapter plate, and M10x1.5 studs for the turbo side. M10x1.25 or Metric fine (1.0) may have been a better choice...but its difficult to get the countersunks especially....I could have used FE3 exhaust studs for the other. The nuts I used in the photos will not be the final ones, I'll use some aerotight nuts so that they dont come loose on the car.....in the past I have used ordinary shakeproof washers, they seem to stand the test of time.

I have no shortage of metric ISO bolts nuts and washers..

As for tightening the csks I used an allen key and tightened them as much as the key would allow without snapping the tip.
 

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Nice work.
I used countersunk screws as when you counter bore and use ordinary cap screws,
Most flat heat (countersunk) screws are not hard enough and can't take the very high temperature though.
 

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Discussion Starter #14
Nice work.
Most flat heat (countersunk) screws are not hard enough and can't take the very high temperature though.
I've done this before, and havent had any probelms so far...
I used M8 csks to hold the adapter plate to the manfold on my turbo GC...theyve been on there now for 7 years...Admittedly spirited road driving isnt the same as racetrack use!

The M10 has a bigger head area so should be better again..
Mind you I am using the same grade of csk as the cap heads that youd normally use for this...I have also used A2 stainless to do this job, seems to work ok too.

Fred, I'll check out the nordlock washers...thx
 

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Admittedly spirited road driving isnt the same as racetrack use!
cough-bullshlt-cough, depends on the size of your nuts :p

I've had smoke pouring off my rear pads on the road before, and many times on the front before I got wise and started using decent pads etc...

A heat cycle is a heat cycle, if it gets hot and just stays hot, then that's all its doing. how hot might change things a bit, but... bolting a plate to a chunk of iron isn't exactly high tech and difficult to get right :) i.e. it will be sweet. Nice job!

Fred, I'll check out the nordlock washers...thx
No worries :)
 

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very nice work.

I don't doubt that taking out the old studs was the most time consuming part - reminds me of when i was removing 2 stripped studs from mine. First i snapped it, then tried using an easy-out and snapped it haha. Tried drilling it, but that easy-out was not gonna be drilled any time soon. Good thing i had a spare manifold.
 

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Discussion Starter #18
Yeah, you've got to be careful using easy outs...

Its even just as bad to snap the drill bits off. which I did the other day drilling the studs out of my TD05 exhaust housing...thankfully you can drill from the other side, so did until I hit the remnants of the drill bit, then used a drift pit and hammer to knock out the broken drill bit...

I usually start by centre punching the end of the stud, start drilling it with a 5/64" bit then work my way up another 1/16" and keep going until I am almost in the thread, then tear out the rest of the stud with a HSS tap.

The key is to use lots of lube when drilling, and make sure you give the drill bit tip time to cool..and use HSS drill bits at least.
 

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I usually start by centre punching the end of the stud, start drilling it with a 5/64" bit then work my way up another 1/16" and keep going until I am almost in the thread, then tear out the rest of the stud with a HSS tap.

The key is to use lots of correct cutting fluid (lube) when drilling, and make sure you give the drill bit tip time to cool..and use HSS drill bits at least.
Good advice ^

Thought I'd better clarify such that people didn't go lubing it with something like grease or oil though. The right stuff makes it so much easier. The wrong stuff can make it worse.
 

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Cutting through a broken tool sucks. I've done it before but to do so you need patience and to regrind your own drill bit to 145deg and over.
 
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