I've got a slight boost prob only boosting at 0.5 bar

It was caused or i thought it was, by some split hoses linking the boost control solenoid, actuator and compressor housing all via a t-piece.
I replaced them with what i thought like for like some silicone hose, however this is where the problem started
I learnt that in one of those hoses was a small brass restrictor that regulated the boost, so eventually subaru ordered in the correct parts i needed (albeit the hose looked a touch short)
I inserted the restrictor in the hose tonight and then fitted said hose to car..

Now this is where ive had fun and games i fitted the hose so it came off the compressor side, (both ways round as when i blew in the hose one way allowed more air than the other) i've also fitted it coming off actuator side pipe as subaru really didnt help with where to put the hose Reset the ecu both times and still doesnt feel right..

Now upon inspection after the 2nd attempt my turbo itself was smoking

After sh*tting myself and getting a mate to check behind the car, we concluded there must be an oil leak onto the turbo. Would this affect the boost in said way?? Another area i looked at is the brass t-piece i used as the plastic one disintegrated upon removing original hoses. Could this be another area i should be looking at and replace with a plastic one as before.

Can someone help please

 

 

The restrictor goes in the short length of pipe between the turbo outlet and the t-piece so it is limiting flow to the actuator and the boost solenoid. It's not always possible to say exactly what size restrictor may be in a particular model year/ type car so it may be that the restrictor you have been supplied is not the right size for your car/ turbo combination. The smaller the hole in the restrictor, the higher the possible boost level will be ( I think around 4psi at the actuator will start it opening ). If you keep going smaller you will reach a point where the boost pressure exceeds the safety level set in the ECU and you'll get fuel cut. My UK MY00 with TD04 had a 1.2mm brass restrictor and when the turbo was replaced with a larger VF30 a 0.9mm restrictor was needed. The 0.9mm is a plastic one and it is easier to blow through it in one direction. The mapper who tweaked mine for the VF30 reckoned the brass restrictors flow differently to the plastic ones for a given size.
Kevin