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Hi all , yep me being me can't be happy with a std WRX TD04L turbo so a few things going on behind the scenes .

Long story short - Rex turbos suffer from using an undersized turbine - even for a std Rex .
Factory fix for the Jap home market was a different Mitsy hairdryer (TD04HL vs TD04L) with the larger turbine and slightly larger trim compressor wheel .

Subie spec TD04HL's are very hard to find info on let alone find the turbo itself . One contact is in Japan ATM looking for them amongst doing other things .
Meanwhile I've been researching Volvo TD04HL turbos because if anything some of their turbine housings are better designed than the Subie type ones and they can be had in the same 6cm size . A new contact in Adelaide is sending me a "straight outlet Volvo 6cm TD04HL turbine housing" and then we will go about mocking up an up pipe to fit the non std three hole flange .
I was always going to have to run non std flanges (for an EA82T) so it means using Volvo spec ones rather than EJ spec ones .
One good thing about these Volvo housings is the 2.75 or 3" round three bolt outlet - very easy to make the down/dump pipe .

More as comes to hand , cheers A .

From the previous owner the outlet hole is 2.5" / 63.5mm diameter , with luck I'll have this housing today .

One further about TD04 turbos VS EA82 VF ones is the size of the turbine and compressor housings .
I'm pretty sure the increased size of them forces you to mount the centre line of the turbo higher than a std one would be - and the std one is borderline too high IMO for the water cooling system to thermosyphon properly when the engine is shut down at running temperature .
From what I can see the turbocharger is the highest point in a single turbo EJ engines cooling system and I'd say it's the reason why they have that raised water reservoir so that it's higher again than the turbocharger .
If the turbo was the highest point water would boil inside it to form steam pockets and steam doesn't cool like water (even hot water) does .

For us making or using Subarus reservoir shouldn't be difficult but we will have to find ways of sealing the radiators filler point because it will no longer be the highest point either . If I can't find a propper sealing cap then I may have to run a higher pressure one there and use a std pressure one on the new reservoir .

Cheers A .

Housing arrived yesterday and looks good , only 9000 k old .
Will compare with Subie TD04L soon .

A .

nice let us know how it goes

You have refered to the WRX TD04 and the Volvo TD04 but i found this image on a Subaru Justy forum and thought you might find it useful.

Its a SAAB TD04L 15T beside a Fiat Uno IHI VL2

Gannon I gave up on those TD04L's/HL's because there was no evidence to suggest that I could get away with a larger turbine and not increase the boost threshold .
The only way to have a hope of doing this is to use a lower friction ball bearing center section and to have some say in which turbine and compressor wheels I wanted meant going with a Garrett unit .

I should have it tomorrow and then it's a case of setting up non std lines and pipes to make it fit and work .

Even with a 6-8 lb actuator it should make a mockery of the std computer and injectors , 250 Hp turbo on 105 hp comp and injectors .
With the ViPec computer and larger squirters it should go quite well .
I don't aim to drill this engine because its cost too much and I think the gearbox is a bit fragile for super duty , being very adequate is what I'm after and wasting a few Libs/Forrester's could be amusing .

Cheers A .

For us making or using Subarus reservoir shouldn't be difficult but we will have to find ways of sealing the radiators filler point because it will no longer be the highest point either . If I can't find a propper sealing cap then I may have to run a higher pressure one there and use a std pressure one on the new reservoir .

Cheers A .[/QUOTE]

Most of the guys who go WRX/STI into Liberty's (myself inc) just leave the standard radiator cap in place & T in the one that comes from the header tank into the one that comes from the std radiator overflow, what you'll need to do is find somewhere on your radiator to put the pipe from the header tank into, Lib's have a small bleed screw on the top drivers side that is utilised for this.

If I can get my turbo to sit low enough the std L turbo water feed/return system may be good enough .
The problem I think people have when fitting EJ turbos to EA82T's is that the turbo sits higher than the std one did , especially if they weld an adapter plate on top of the original headers turbo mount flange , and it doesn't thermosyphon properly after shut down at running temp .
I'll have to compare an EA82 turbos turbine housing to a VF10's one to see if the housing, mounting face to shaft height , is taller which would also sit the turbo higher than std .
It bog std form the EA82T's turbo is badly placed meaning you can't get the engine side water banjo bolt out far enough to remove it . If your going to do a header and dump you'd move the turbo away from the engine and aim to sit it tad lower if at all possible .

As I mentioned if you had to use a header tank it would be easiest to use a higher pressure cap on the radiator and a std one on the headers filler . That way the highest point has the correct pressure regulation at the header and you can easily link the radiators and headers overflow to the same reservoir for expansion and recovery duties .

A .