Fitting a manual boost controller on TT Legacy

[Raghza]

Alright so the original boost solenoid on my '96 Legacy GT-B is stuck dead and I only get 0.5 bar boost on primary and secondary. I tried cleaning the solenoid, but got no results.
When I disconnected hose 23, the boost was back, so the problem must be in the boost solenoid.
So what I want to do now is to fit a manual boost controller and get rid of the original boost solenoid that's clearly restricting my boost levels.
But where must I connect the manual boost controller? It has two hose connectors like the solenoid, so I believe it connects somewhere near the wastegate between hoses 10 and 23, but where exactly?

It's a basic mechanical boost controller like THIS (http://www.tbdevelopments.com/catalog/images/boost3.jpg). Can I just unplug hoses 10 and 23 from the solenoid and connect them to the boost controller or does it have to be connected somewhere else?

Thanks in advance!

[Telemekas]

http://www.turbosmartusa.com/technical- ... tallation/ (http://www.turbosmartusa.com/technical-articles/manual-boost-controller-installation/)

[Dead91silvia]

Nice! I might be doing this also.... Only thing is, that was for a parallel, not a 2-stage.

[Raghza]

Yes, I've seen all those pictures and diagrams, but if I connect it like this, what would I do with hoses 10 and 23 and the original boost solenoid? Should I just disconnect it somehow?

[Telemekas]

Plug off line 23 from the turbo to the solenoid. Line 10 is just the bleed off from the 2 port boost control solenoid to the intake.Leave the solenoid located in the fender plugged in.

[Raghza]

Nice, thanks alot!
But I'm still not completely sure, where to connect the boost controller. The closest HERE (http://www.turbosmartusa.com/technical-articles/manual-boost-controller-installation/) seems to be the first setup, but I'm not sure.

What I understand is that I connect the boost controller instead of the T-piece coming from the wastegate like shown HERE (http://jsalmi.com/car/boostcontroller/), which leaves me an open end of hose 23 coming from the solenoid. I just leave it open and also leave hose 10 completely connected?

Another solution I found is to connect the boost controller to hose 23 and disconnect and block hose 10 (Greeky mod). Which setup should I choose? The first one is more complicated, but seems like the right way to do it. Any comments?

[Telemekas]

Run the boost controller between the turbo boost port and the wastegate actuator. Use new hoses as the subaru hose has a restrictor pill in line from the boost port to the T.Plug off line 23

[Raghza]

Okay so after a lot of fiddling I got the controller installed. The hose 23 is now just disconnected and hose 10 is still connected at both ends.
However, I still get no more boost than 0.5 bar on both turbos. When the controller is almost shut, I get a bit of overboost, around 0.9 bar, and then it drops back to 0.5 bar and stays there. When the controller is a bit opened, it's just 0.5 bar and not more. When I open it even more, it makes no difference.
Should I disconnect hose 10? If so, should I block it from the engine side?

[Telemekas]

Hose 10 is the bleed off from the subaru 2 port boost controller to the intake.If hose 23 is disconnected and blocked off their is nothing going through hose 10.
0.5 bar is the approx wastegate actuator spring pressure.The boost controller should allow you to restrict the amount of boost the actuator sees hence raise boost.If the boost controller is totally shut you would be free boosting.
In addition Hose No:2 going to the solenoid box from the boost port under the IC.Disconnect the hose from the solenoid box. Block the hose and cap the solenoid box port.This will stop any boost lost to prespool from the primary turbo.

[Raghza]

Just to confirm your story, I disconnected hose 10 and blocked it on the engine side, so both hoses that connect to the boost solenoid, are now just cut loose. And like you said, nothing changed. :)
But I am gonna try that thing with hose 2 and hope to see some improvement.

So now that I don't have the boost solenoid connected anymore, are there any other solenoids that may restrict my boost to 0.5 bar and might need cleaning?

[Telemekas]

Block and cap the hose No 2 ports.This will disengage the prespool boost solenoid.
Do an ECU reset as you may be in limp mode.

[Raghza]

So I blocked hose 2 and did an ECU reset, but still nothing. Ofcourse I've only done 10km after the reset, but I don't think the boost is coming, since I've always had normal boost levels right after the ECU reset.
What the hell is going on lol?

Right now what I have done is:
- fitted the MBC between the turbo boost port and wastegate
- blocked hoses 23 and 10 coming from the boost solenoid
- blocked both ends of hose 2 near the solenoid box
- did several ECU resets

And I still get only 0.5 bar boost on both turbos (ofcourse, when the secondary turbo kicks in, the car goes a lot better, but it's still at 0.5 bar, not 1.2 bar like it used to boost, when the solenoids were working and I didn't have the MBC) and adjusting the MBC for more boost doesn't change anything.

EDIT: Starting to think about it, could it be that my boost controller is connected backwards? I connected the bottom connector, through which you can blow air when the controller is open, to the turbo and the other end at the wastegate. Is that correct?
Is it supposed to connect like this: http://i284.photobucket.com/albums/ll19 ... tled-1.jpg (http://i284.photobucket.com/albums/ll19/TweeT91109/Untitled-1.jpg)
If it is, then I think that mine is connected the other way round...

[Raghza]

Alright so I threw away the MBC and went back to stock again. Everything was connected properly, but the MBC is just not the way to go on this car.
However I managed to cycle the original boost solenoid by connecting 12v straight from the battery to it (doesn't matter which way, btw) and it seemed to be working well. However I still only get 0.5-0.6 bar boost on primary and 0.5 bar on secondary, so tomorrow I'm gonna refurbish the solenoid box and check the pressure relief valve, to make sure it's working.
But now I've tested it and came to a conclusion that a manual boost controller really doesn't work so well on a twin-turbo Legacy or is really difficult to set up properly.

[Mark in NZ]

You obviously have a problem somewhere in the system - an air leak maybe?

I'm running a manual controller exactly as telemekas describes and have a perfectly consistent 1.1 bar on primary and secondary, it works exactly like any other turbo car and have done it on 3 TT legacies of my own before