grim_d
Unlikeable idiot.
- Messages
- 4,218
- Location
- Scotland - Ayrshire
Evening,
Car is my JDM Subaru Legacy GT, 2.0 Turbo EJ20X (Dual AVCS).
I've been trying to figure this out for ages, initially thinking it was down to the mapping and a low Wastegate duty cycle, but it seems not and I'm not having any more mapping done until it's solved.
Basically I cannot acheive the boost that the ECU is targeting, it targets 1.2bar and I can only achieve a maximum of of 1.1bar, the turbo should easily be capable of this. All other systems appear to be working correctly, nothing iffy reported by my mapper.
I'm basically trying to establish where the problem might be and looking for some confirmation on my methods.
The system has been leak checked as much as is possible, it's not easy on a Subaru! It pulls good vacuum. (0.7bar ish)
The boost control solenoid is clean and confirmed working.
The restrictor pill is present.
I've had the intake off to check the compressor for damage and the shaft for wear, all seems good. Turbine requires a lot more dissasembly so not yet checked.
So...I'm really trying to establish if the turbo is actually capable of more boost, I kind of suspected the Wastegate actuator. To my knowledge it has a 0.55bar spring in it.
It's next to impossible to get to the actuator lines so I have attempted testing in the following way...removed the line going to the control solenoid and bunged it, this should give me a maximum boost as determined by the actuator spring as nothing can be bled off, I got 0.55bar boost. Seems ok then.
So I need to go the other way now and prevent the Wastegate from opening and attempt a (controlled) overboost scenario.
I left the line open to atmosphere and went a run, got 1.1 bar, I realise this is effectivley a boost leak however small so tomorrow I'm going to plumb it back into the intake and try again. I can't imagine it will make much difference.
Ideally I would pull the line from the actuator and bung it but I simply cannot get to it without major dissasembly.
Does that sound logical? Any other ideas?
Thanks!
Car is my JDM Subaru Legacy GT, 2.0 Turbo EJ20X (Dual AVCS).
I've been trying to figure this out for ages, initially thinking it was down to the mapping and a low Wastegate duty cycle, but it seems not and I'm not having any more mapping done until it's solved.
Basically I cannot acheive the boost that the ECU is targeting, it targets 1.2bar and I can only achieve a maximum of of 1.1bar, the turbo should easily be capable of this. All other systems appear to be working correctly, nothing iffy reported by my mapper.
I'm basically trying to establish where the problem might be and looking for some confirmation on my methods.
The system has been leak checked as much as is possible, it's not easy on a Subaru! It pulls good vacuum. (0.7bar ish)
The boost control solenoid is clean and confirmed working.
The restrictor pill is present.
I've had the intake off to check the compressor for damage and the shaft for wear, all seems good. Turbine requires a lot more dissasembly so not yet checked.
So...I'm really trying to establish if the turbo is actually capable of more boost, I kind of suspected the Wastegate actuator. To my knowledge it has a 0.55bar spring in it.
It's next to impossible to get to the actuator lines so I have attempted testing in the following way...removed the line going to the control solenoid and bunged it, this should give me a maximum boost as determined by the actuator spring as nothing can be bled off, I got 0.55bar boost. Seems ok then.
So I need to go the other way now and prevent the Wastegate from opening and attempt a (controlled) overboost scenario.
I left the line open to atmosphere and went a run, got 1.1 bar, I realise this is effectivley a boost leak however small so tomorrow I'm going to plumb it back into the intake and try again. I can't imagine it will make much difference.
Ideally I would pull the line from the actuator and bung it but I simply cannot get to it without major dissasembly.
Does that sound logical? Any other ideas?
Thanks!