Jump to content
SAU Community

Recommended Posts

  • Replies 886
  • Created
  • Last Reply

Top Posters In This Topic

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.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • I came here to note that is a zener diode too base on the info there. Based on that, I'd also be suspicious that replacing it, and it's likely to do the same. A lot of use cases will see it used as either voltage protection, or to create a cheap but relatively stable fixed voltage supply. That would mean it has seen more voltage than it should, and has gone into voltage melt down. If there is something else in the circuit dumping out higher than it should voltages, that needs to be found too. It's quite likely they're trying to use the Zener to limit the voltage that is hitting through to the transistor beside it, so what ever goes to the zener is likely a signal, and they're using the transistor in that circuit to amplify it. Especially as it seems they've also got a capacitor across the zener. Looks like there is meant to be something "noisy" to that zener, and what ever it was, had a melt down. Looking at that picture, it also looks like there's some solder joints that really need redoing, and it might be worth having the whole board properly inspected.  Unfortunately, without being able to stick a multimeter on it, and start tracing it all out, I'm pretty much at a loss now to help. I don't even believe I have a climate control board from an R33 around here to pull apart and see if any of the circuit appears similar to give some ideas.
    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
    • You don't have an R34 service manual for the body do you? Have found plenty for the engine and drivetrain but nothing else
×
×
  • Create New...