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No if I pressurize the system with a compressor the only leak is the tappet cover breather. Air would be going past the piston rings and or through the other breather that's hooked to the plenum and coming back through. What exactly do you want to see?

Air shouldn't be going past the piston rings..

You've Got some serious issues.

And when runnin that my boost, why the hell aren't you running a proper electronic boost controller?

Skimping on one of the most critical parts?

I was only going to run what the wastgate actuator would push originally. That's why I haven't got a boost control yet, when I get it holding boost il buy another electronic controller.

Focus on the air leaking with the pressure test, I just run off the actuator and mine runs very well. The lack of an electronic boost controller is definitely not the issue here.

Can you describe the steps you use to peform the pressure test?

And when runnin that my boost, why the hell aren't you running a proper electronic boost controller?

Skimping on one of the most critical parts?

I ran 19PSI through a simple manual boost controller and it holds extremely flat through the rev range. Do you really think the cost of an electronic boost controller is worth it?

Have you tried wiring it shut and very carefully driving to see if you can hit 20 psi higher in the rev range? I thought they might have done that on the dyno

Have you tried a different actuator yet?

Simple test if you like, its a stupid one, a dangerous one but at least you will know where you stand.

Disconnect the air feed to the actuator and block the hose. Run the car and CAREFULLY using your foot on the accelerator to control boost and see what happens. This is dangerous stuff as the car will boost as much as the turbo can so it is all up to you to control the boost with your foot. If you see boost rise to 22psi slowly back your foot off and see if you can maintain 22psi. If it keeps rising back off. Your boost graph shows fall off as soon as you hit 22psi so in theory if there is a boost leak, the moment you hit 22psi will create enough pressure to give you this big drop you are having.

I think it might be safe to say that if your car powers past 22psi of boost, say you hit 25psi for example, at 4krpm, then I would say you don't have a leak. More pressure will create a drop in boost if there is a hole somewhere. If you find your self having to mash the accelerator heaps to control the boost then you may have a boost leak.

Seriously though, boost leaks.... You should hear the damn thing.

XR6 will out do you at the lights with a turbo which comes on at 3600rpm, its what happens after that that really matters lol.

I don't like continuously feeding air to the intake when doing a pressure test. Does your pressure tester have a gauge attached to it? Mine was a home made piece, no gauge but there was no need. As soon as I put air in, I heard my leaks, fixed them up and bam no more leaks.

IF you don't hear the leak, its more likely than not that DON'T HAVE A LEAK.

Edited by SargeRX8

I haven't got a different actuator yet, il try the no boost line test again, last time I didn't have much empty road so I mashed it to 30psi and backed off because of traffic.

It was a non turbo xr6 from about 60km up.

My tester has a gauge in it. I made it at work.

3mm of preload

As others are saying, if you can tighten the preload. If you made 30psi clearly you do not have a leak. If you have a leak which only gives way at 22psi, it will definitely give way at 30psi very quickly. Dude get a different actuator and be done with it. I am almost CERTAIN it is the actuator spring.

Leaning towards this also...

However, if the losing all power after 5 minutes thing is still an issue, that doesn't seem like an actuator symptom. That sounds more like a restriction of some sort causing heat soak.

I think the next step has to be trying a new actuator. If that is ruled put then you can start thinking of other possible causes, but right now it seems like the most probable cause.

Edited by Hanaldo

Try a different actuator for sure, as for the loosing all power are you running a standard ecu with nistune? If so is it going to knock maps.

Copy your main fuel and timing maps over to your knock maps, pull a few degrees from the knock map and add a touch fuel to fueling map(For alittle added safty)

Now see if the loosing all power is less harsh. Then retune.

There is deffinately tune issues, the change over from vac to boost is rough. And heat soak make it feel very dead after a few minutes.

It's not possible to create more preload on the shaft, but I could just put washers in to pull the actuator back.

I don't have the password for the nistune so I can't touch it.

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