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NADS. ZD30 NADS steps and logic with diagrams

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#1 · (Edited)
Buying a used ZD30DI can be tricky, I would not buy a vehicle between the years of 2000 and 2003 without factoring in a rebuild or crate engine replacement. Once you get into 2003 the engine is much improved and later models even better. I would buy a clean 2004/5 tomorrow no worries. My own vehicle is a 2000 DI that I bought new and serviced regularly and didn't thrash, it grenaded at the end of 2006 (not all do as mentioned below) at the end of a 1000k work trip home, I had done around 6 of these that year where I jumped in the car drove quickly 1000k to the work site stayed a week and went back home, the repetition, high speed and not having an EGT gauge were big contributing factors.

The engine was rebuilt and the search was on to make the old girl as reliable as I possibly could, so the following is the direction I took mine to maximise it's life, 8 years down the track she is stronger than ever.

Particularly for older ZD30’s, don’t for one moment think that fitting all this stuff will save your early ZD30 from cracking heads and pistons, the reasons this happens are quite complicated and a vehicle can sit on the threshold of blowing up for very long periods of time and then one day the combination is right and it goes, but, rest assured for every ZD30 that blows up there are a myriad of it's brothers that didn't, you only hear about the bad ones not the good ones, as said the reasons can be complicated. If you have rebuilt a ZD30 I would do this straight away. I did around 25-30,000k after my rebuild before I got into this.

NOTE: We occasionally hear of repeat engine blowups, most of the time this is a direct result of skimping on the head when the original blowup occurred, if you are going to rebuild, do not short change on the head, do it properly or it will come back to bite you later and you won't enjoy the years of trouble free motoring you should have.


Nads steps and logic part 1.


This mainly applies to the ZD30's built up to around 2005, after that the ECU was a little better at controlling boost, but still applicable right up to the advent of the CRD (which doesn’t usually require the Dawes Needle combination but may be beneficial in some cases).

I would strongly recommend that between each step, drive the vehicle for a week or so to see what happens, the education you will gain is well worth the wait, steps 1 and 2 can be done together and after a learning period so can 3 and 4, leave a gap and do 5 as this one may cause it's own little problems as mentioned in the step.

1. Fit EGT gauge, this is the single most important thing you will ever do to your troll, this way you get to see what is happening in your engine under the conditions you normally drive with, you will be surprised even shocked and you will change your driving habits and style. Treat 550C as a usable maximum on a DI.

2. Fit Boost gauge, this way you get to see the effect of boost on EGT, by this time you have modified your driving and will see the effects of ECU boost control on a standard vehicle, if you have an early one it will be quite erratic at times, particularly at highway speeds.

3. Fit Dawes and needle valve (or whatever manual boost controller you decide to fit, they are basically all the same, NOTE, the only setup difference between Dawes and Tillix is the Dawes has a built in Vacuum T and the Tillix has a separate vacuum T) as described in articles you will find with a search. The reason this is done is to take control of the boost away from the ECU, which will make the boost jump around and in some cases drop right off, this may result in very high EGT (the boost on my old girl would drop off to 2-3psi at around 115k then on hitting a hill and powering the EGT would skyrocket, later model ECU's did have better control but still not great). The boost will become linear and EGT will respond better. This step entails bypassing the vacuum switch beside the airbox, I have my system outlined in my Albums and just above in post # 6. Suggest fitting a good quality needle valve such as a DV06 1/8” BSP valve, Darren Dawes has a new needle valve available with 10 turns open to close so it is very easy to adjust, most good needles will have at least 6 turns and you should only be open 2 turns at most otherwise your boost will drop off too much. The needle can be situated under the bonnet but for greater flexibility (especially if you tow) put it in the cabin, there is a spot under the steering wheel where it will slot in quite neatly. My method of setup is to close the needle while you set the max boost, once you are happy with that, set the needle to achieve the spoolup rate mentioned below

3.1 Set the needle to spoolup the turbo at around 5-6psi @ 1500rpm, 10-12psi @ 2000rpm, these are rough guides not necessarily hard and fast rules (we thought at one stage that fast spoolup would cause turbo damage but we really have not experienced that, my current spoolup rate is 21psi under 2000rpm but it took a lot to achieve that). In doing this exercise you will learn more about the effects of the needle on spoolup and performance. Remember that low boost = high EGT, high boost = higher fuel usage, there is a nice spot somewhere in the middle.

3.2 When you fit the Dawes Needle combination (or whatever controller you have chosen) start low, suggest 13-14 psi and see what happens, adjust higher later if your confident, usually limp will occur around 16psi particularly under 3 grand, but this is MAF voltage related (see limp mode note below). The secondary part of this is VNT adjustment but this should be thought about and investigated carefully before attempting, many problems have occurred due to loss of original position. But having said that it is actually quite simple, just a little daunting at first, see VNT Adjustment in one of the albums in my signature.

3.3 This is my dual Dawes setup Dual Dawes and Needle valve on Nissan Patrol ZD30 DI - YouTube
Also a clip on dismantling a Dawes and adjusting it Dawes Valve Dismantle and Adjustment - YouTube

Dawes Note: It is not uncommon for the spring inside the Dawes to require a stretch, Darren has been asked about this and he says stretching is not a problem, small variances in spring compression during manufacture can have an impact. To stretch, take a measurement and stretch 5mm only and try again. From memory mine went from around 12psi at full adjustment to 15 at half way, on rare occasions a second stretch has been required.

NOTE 1: There is an optional HD spring available from Darren, Dawes Devices by 3 Bar Racing Inc. | Dawes Devices, the Best Manual Boost Controllers

NOTE 2: The needle valves purpose is to slow spoolup rate, this is done by opening the needle valve (rotating to the left), which feeds in clean air from its source and lessens the vacuum available to thye VNT, if opened too far there will be a severe drop off in performance. Closing the needle valve (rotating to the right) puts the vacuum back to maximum effect on the VNT and putting spoolup to maximum for the conditions. The needle valve can also be used to improve fuel eco out on the highway by adjusting cruising boost down a little

Note 3: With the advent of the remap for the ZD30DI in late 2017, limp is a thing of the past for those that choose to do it, this allows me to use 21.5-22psi, which we consider a safe 'boost' for our std Garret 2052. I have also stopped using my Dawes and needle valve, after much experimentation I am using a device called a Digibooster, it's from a Scottish Company, this controls max boost as well as maintaining turbo vanes in optimum position, this gives greater 'driveability' and can marginally improve fuel eco.

There is a separate system these days that uses 3 needle valves, have placed a schematic Supplied by Bidja's in Post #6 with the other Dawes Schematics.
 
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#2 · (Edited)
Nads steps and logic part 2.

Limp Mode Note: When I say limp will occur at around 16psi, it is not generally the outright boost that causes limp, this usually relates to elevated MAF voltage due to some mods or a sensor failure, an ECUTalk puts a different perspective on it showing the relationship between Boost (under high load) and MAF voltage. The MAP sensor really only protects against quite high boost, mine will go to pure boost limp via the MAP sensor at around 26psi, have seen mine hit well over 20psi in the early days of setup, but I know from experience that if I held 3.98v under 3000rpm for a few seconds I would have limp mode and no code would be thrown. One thing to consider if you have a manual, load and therefore the upper MAF voltage will change slightly between 4th and 5th gear, sometimes enough to go back to limp, so final setup should be done in 5th, if you want to wring the maximum out of it. Please note that people often refer to Overboost with a ZD30, over boost is overrated, your vehicle can spike to 20 psi without a worry but if it hangs around there for several seconds the ECU will respond to the elevated MAFv and induce limp.

If somehow I can maintain 3.97v I have no problem, so lets look at the needle valve, I have a DV06 that has 6 useable turns at my disposal (some have 5 or less) at 18%tps on level ground I have a MAF reading 3.71v, if I open the needle valve the full 6 turns that drops to 3.59v which is a drop of 0.12v, the adjustment is fairly linear as 3 turns open drops it around 0.06v, this is repeatable as I have done it many times.

So if the vehicle in it's raw state hits 4.0v at 3000 and opening my valve 6 turns brings that down to 3.88v I've defeated limp, 3 turns would bring that down to 3.92v and I've still defeated limp. But if I'm hitting 4.10v (and mine would flash to 4.20v in the early days and go to limp) full open may just defeat it but halfway won't, then we either reduce boost at the Dawes to try and reduce MAF (but as said some mods will change these things independently) or we adjust the VNT grub screw down slightly, 1/3rd of a turn usually will do it, to get a result.

NOTE*Chronic Limp Mode can be experienced when very high boosts are used (therefore very high MAF's), these can be overcome with units like the TurboSmart FCD2 or the JayCar Voltage Interceptor, I have used both with success but the JayCar unit will cover multiple limp stages with ease. The latest for the DI is an ECU remap to sort out limp, I can hit very high MAFv (with my mods I've seen 4.83v under extreme acceleration) now completely limp free. The Company that did mine is East Coast Performance Tuning at Tuggerah, Harley is the Tech guy and he knows his stuff, I don't trust too many people doing things on mine so I did a lot of research first.

EDIT: Since doing this mod I have played a little more, have reconnected the vacuum solenoid with pretty good results, this improved my fuel eco without any loss of performance and the VNT is doing what it was meant to, adjusting itself to suit conditions rather than stay 'full on' all the time (I still use my Dawes to control maximum, tried using Vac Sol for this also but boost would go to dangerous level as times so I went back to Dawes control of maximum). This may not work for everyone, I had to clean out and lubricate the Vac Sol as it had a chatter when I first put it back on line. I connected my laptop to the ECUTalk and did several hours of data collection with interesting results, there is a small hiccup that occurs from time to time but this is being investigated but it causes no issues and I've driven many thousands of K since doing this, results are too long to put in here but I have written them up in my build thread (see link in sig, index in first post).


NOTE* Cold limp is often experienced in colder climates, this is usually caused by the denseness of the cold air, when the engine bay warms up cold limp will usually go away, it also can be a sign that you are very close to the max tolerance on MAFv.

4. Fit a catch can, this is also quite important, oil mist from the rocker breather mixes with soot from the exhaust via the EGR. The resulting thick black paste can partially block the throttle body and manifold and could cause problems with the air fuel mixture in the various cylinders, it does not take long for this “paste” to start building. The oil mist alone coats the internals of the Intercooler and reduces its efficiency. I strongly suggest moving the restrictor that is inside the original hose into the replacement hose or as I did, make other arrangements to act as a restrictor, it is there for a purpose. NOTE: a clean out of the IC is a good idea at this time, it could result in cooler running temps and also you can inspect the IC inlet at any time after to see how well your catch can is working. To clean, remove the IC and wash out with turps etc, then fully rinse and dry before refitting.

5. Block the EGR. A thin plate, stainless or gal (which I used) of around 0.7 – 1.0mm is good, any thicker and you start to distort the EGR housing. My preference is to block it at the inlet manifold end rather than the exhaust end, I did it some years ago exactly as Askniss outlines it in the bible no problems then or now. I put the original gasket back in on the manifold side but I also coated all the components with Stag jointing compound to guarantee a good seal.

6. I have come to consider the glow plug timer mod http://www.patrol4x4.com/forum/zd30-di-engine-3-litre-71/glow-plugs-why-missing-tips-59903/ an integral part of NADS, I kept putting my conversion off due to my dyslexia with electronics but it turned out to be actually quite simple, believe me if I can do it anyone can do it.

7. I also consider an ECUTalk a good companion especially for the early models, with MAF and Temp readings (to mention a few) right in front of you it is a very handy tool, these can also be linked to internal audible alarms.

8. Everything else after this is mainly for performance gains, bigger IC, Chips, bigger exhaust (which will impact on the turbo spoolup rate), etc, etc, although I like the lift pump/spill line exercise to give the IP a good rest after all it's previous hard work dragging that fuel all that way, this is quite a common mod in the US on the VP44 IP's used on some of the Utes from the early 2000's there. You will be amazed at the low down performance it brings.
 
#3 ·
Neat little write up

For those getting it all together, this is a pretty good writeup.

A question -- with regards to the 5-6 psi at 1500 rpm and 10-12 psi at 2000rpm, in your learned capacity should there be any difference between auto and manual.

Why I ask is my truk is auto and I have found that 4-5 psi boost at 1500 rpm on a road surface of about 5% incline and 8-10 psi boost at 2000 rpm to be more acceptable. (2004 3L di not towing).

Towing a 1.8t load on a flat road (cruising along down the Newell Hwy with cruise control ON), I see 92 klm/hr, 1900rpm, 9 psi boost and 290 deg EGT. which gives a fuel consumption of about ( dependant on OAT, tyre pressure etc) of about 14-15 L/100 k's).

How do these figure compare to your rig.

Thanks - Cheers

my 2 bobs worth
 
#5 ·
For those getting it all together, this is a pretty good writeup.

A question -- with regards to the 5-6 psi at 1500 rpm and 10-12 psi at 2000rpm, in your learned capacity should there be any difference between auto and manual.

Why I ask is my truk is auto and I have found that 4-5 psi boost at 1500 rpm on a road surface of about 5% incline and 8-10 psi boost at 2000 rpm to be more acceptable. (2004 3L di not towing).

Towing a 1.8t load on a flat road (cruising along down the Newell Hwy with cruise control ON), I see 92 klm/hr, 1900rpm, 9 psi boost and 290 deg EGT. which gives a fuel consumption of about ( dependant on OAT, tyre pressure etc) of about 14-15 L/100 k's).

How do these figure compare to your rig.

Thanks - Cheers

my 2 bobs worth
Thanks, I have been through many steps in mine. Prior to the Cross Country Installation I was running 6psi and 12psi respectively and it had been higher than that with no issues. My current settings are 4.5psi and just a touch under 10psi at the same, my reasons for this are that something changed with airflow when the CCIC went in and a limp issue started, this was addressed with a Turbosmart FCD2 fuel cut defender then a second low level limp appeared and the only way I could get rid of that was to lower the spoolup rate further (4.5 and just under 10) and also have less than 15psi at 2500rpm, the interesting thing was I lost no performance in doing so. I have a brass shim under the VNT grub screw which I have beaten down in thickness (starting at 0.025" to completely eliminate the low rev limp) from time to time and it is time to push the boundaries again just to see what happens so I will be taking the hammer to the shim quite soon, stay tuned.

Yes Auto's are a little different especially with regard to ratio's as you already know and I don't profess to be any sort of expert on them but my numbers are quite close to yours. I mentioned this recently in another thread, I have a slightly higher EGT since lowering the spoolup rate but it puts me in a place where I am happier. Unloaded on a flat road I am at 5.5psi, 2600 rpm and 290C and I have 18psi on demand, loaded is just marginally higher but I don't have an accurate loaded number documented at this time.

I will be updating my EGT survey shortly as I have not done this accurately since the last round of mods.
 
#6 · (Edited)
Bloody hell! I kept a reserve but it's run out of time already.......

NOTE: The vacuum canisters were deleted from the range somewhere around 2001/2. So, if your vehicle doesn't have one, disregard it and carry through to the next bit of hardware.

If your canister has broken (and it is not uncommon for the nipple to break off when trying to remove the hose) you can just remove it and bypass without consequence.

Text Diagram Technical drawing Plan Drawing


The dual Dawes setup has proven to give me slightly better fuel economy in traffic and smoother operation when accelerating away from lights etc, off course this depends on your spoolup rate, slower spoolup smoother action.

Text Diagram Technical drawing Line Design

EDIT: A much later system without the VacSol, Dawes/Tillix with 2 needles, pic supplied by Bidja.
 
#7 ·
Sorry to post in, but is there any point retaining the Vac Canister? I bypassed mine and saw no fluctuation, but a more easily controllable boost and more responsive boost under load and acceleration. Also more reliable as I deleted it because it cracked and was leaking vac
 
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#8 · (Edited)
There may have been an issue with yours as I noticed no difference in mine at all after removing it, after the trial I put it back as there was nothing wrong with it but I have since put a small surge tank at the VNT to relieve dawes bounce I was suffering which showed up on the dyno and was particularly noticeable in low boost mode with several blips of around 8hp occuring, working more smoothly now.
Auto part Fuel line Hose Automotive fuel system Pipe
 
#10 ·
With regard to recent questions. When setting up the Dawes system you really do need to fit the needle valve, if you don't the ECU controlled vacuum switch mentioned in post 1 and shown in post 6 drawings, will still have control of the vacuum to the VNT meaning the boost will still fluctuate at different times and will not be directly linear with throttle control.

I absolutely recommend fitting the needle valve in cab to give you the flexibility of adjustment on the fly, it is quite handy when towing and additionally I use mine more now to allow me to retard the water injection point on long trips (my w/m injection is boost controlled), so it is still quite a handy device even though I have found the almost perfect VNT grub screw adjustment over time.

A very simple method of setting up the system is to close the needle valve and set your Dawes, as said in post 1 start low 14-15psi, once you have this you can start to play with the needle and set your spoolup rate as described below as well, remembering spoolup rates described are a guide only if they are a bit over I have come to realise it isn't the end of the world, doing a few hills and seeing EGT effect will be the judge.

I would appreciate some feed back as sometimes we lose sight of how daunting it can be to do this, I do remember when I first set mine up and drawing all this out in my head, if we can make the explanations more simple let me know where the problem areas are and I will make adjustments.
 
#12 ·
I would appreciate some feed back as sometimes we lose sight of how daunting it can be to do this, I do remember when I first set mine up and drawing all this out in my head, if we can make the explanations more simple let me know where the problem areas are and I will make adjustments.
Hi ya,
Thought i would give a little feedback as a recent installer of the Dawes setup. The process of read as much as possible on the forum, compare various NAD's processes then have a go worked for me. Tis a daunting thing to modify a system that on the surface appears to be Ok. It would be nice to know that post Dawes setup boost levels remain relatively steady during "normal" driving, i see consistent boost levels and lower EGT's without the boost fluctuation experienced when the ECU had control. After a bit of fiddling I can get to boost at 14 psi but assume there should be more to be had. As a mod this would be one of the better ones with immediate improvement in drive-ability and even the missus commented that the engine seems to sound better, not working as hard as it used to.

I set the Dawes up with needle valve open just enough to seat the VNT actuator on its stop, kinda hard to see as engine running the whole lots a jiggling, then someone suggested a 7mm thread gap on the Dawes valve as a start point. That done went for a spin and reduced the thread gap some more to where it is today.

If I could add anything to the NAD's document it would be expected outcomes, eg, highway driving, 100km/hr no load, boost should sit around 10psi, egt's around 300 degs as an example. These figures are what I see anyway and assume to be ok.

What i dont know is how this setup will behave at higher speeds, will there be higher boost, eg 120km/hr == 14psi == egt's ??
Still experimenting and still running in the new donk.

Trust this is the type of feedback your after, much appreciate the effort that goes into developing the guides found on here.:)
Thanks

Bill
 
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#12 ·
If someone wishes to keep the vacuum solenoid in the system, especially after a remap, this is one method I played with, can be used with or without the second solenoid, this was just so I could have a preset needle when cruising for better fuel eco.
523170
 
#15 ·
But it already is a sticky, in the first post of the ZD30 DI archives, now I'm starting to question the true value of setting up the archives........

We can always add to it, that is not a problem but exactly what to add, I have spoken privately to several people and have a few ideas, but appreciate all feedback.
 
#16 · (Edited)
Have had a few interesting PM's on this subject, one from Guey on building a database on engine temps under varying conditions, towing etc (like we did with the EGT survey a few years ago, but this would need to be based on ECUTalk and aftermarket gauge readings as the std one just doesn't bloody move.....)

The other from Diesel Tech on building a diagnostic Data Base for the ZD30, this has great potential the more I think about it, we could do it for both the DI and CRD. We could use that as a fault elimination system to rule out certain factors along the way.

Both of these are great ideas.

I'm going on a reef fishing trip for a week tomorrow (bloody rough out there so I have heard today....), it would be good to get some ideas on how we could set this up and make further improvements, trust me I will be thinking of it too between bites :) really. Have a think and PM me your suggestions for this.

Everyone will have noticed we are getting a lot more repeat questions recently, often with just subtle differences, this slowed considerably when we first put in the Archives but we need to have another look at what we can do to help our mates.

Have reserved and soft deleted several posts to maintain continuity when we get started.
 
#17 ·
Skimping - short change on the Head ?

Hi geeyoutoo


NOTE: We occasionally hear of repeat engine blowups, most of the time this is a direct result of skimping on the head when the original blowup occurred, if you are going to rebuild, do not short change on the head, do it properly or it will come back to bite you later and you won't enjoy the years of trouble free motoring you should have.


Saw this thread appear, was reading thru and note your statement above.

Am looking at getting a ZD30 to rebuild (hold as a spare). Patrols are getting up in K's.

I'd like to get your slant on what is considered as skimping or short change with respect to the head when rebuilding a ZD30.

Thanks and Cheers
Q8160
 
#18 ·
Hi geeyoutoo


NOTE: We occasionally hear of repeat engine blowups, most of the time this is a direct result of skimping on the head when the original blowup occurred, if you are going to rebuild, do not short change on the head, do it properly or it will come back to bite you later and you won't enjoy the years of trouble free motoring you should have.


Saw this thread appear, was reading thru and note your statement above.

Am looking at getting a ZD30 to rebuild (hold as a spare). Patrols are getting up in K's.

I'd like to get your slant on what is considered as skimping or short change with respect to the head when rebuilding a ZD30.

Thanks and Cheers
Q8160
Sorry mate been away and only just caught up with this, what I was referring to was heads being welded and otherwise repaired, if I was rebuilding another engine it would be a brand new head and if I could get it at the right price a fully assembled new head, I just think for the amount of money that a rebuild costs, the price of a head is not over the top and it would give me a greater feeling of confidence in the engine.

We put a new head on mine when it grenaded in 2006/7.
 
#19 ·
Hi geeyoutoo,
Sorry for my English, I'm from Kazakhstan and usually we use russian language.
I have 2000 di with implemented single dawes device and needle valve. This has been done more than a year and I'm stell can't get reed from boost bounce under high acceleration.
During today rereading I found difference in your schem and Chaz. I'm talking about pipes.Is it something principle or i should forget about it.
Thanks in advance.
 
#23 · (Edited)
Hi Jan, I can honestly say your English is better than my Russian so if you can understand me we can work through this :). Maybe you are looking at two different setups, there is one where you retain the vacuum solenoid and one where you bypass it. Chaz does in fact have sketches on both but I don't like using the vac solenoid so never did a drawing that included it.

For the non vacuum solenoid, there may be some minor differences between Chaz's and mine but the principle is the same.

There are two separate items here, spike and bounce, spike is when you overshoot and return to setting, bounce is when you overshoot drop below and then stabilise on setting, sometimes bounce can happen a few times before it settles. Boost bounce/spike can be brought on by many things, if you have a lower boost setting on your Dawes and a high spoolup rate on your VNT turbo then it is easy for the boost to overshoot on the Dawes but generally it comes back quite quickly. This is why the needle valve setting is so important and why some of us go to the next step and adjust the VNT grub screw, if you like send me a PM with some more detail, or just post more detail here, what exactly do you have on your vehicle. Control can be improved as I use 18.5psi boost and my spike is roughly 20psi and immediately back to 18.5psi.

Edit: just to make sure, pull your Dawes apart, making sure you count the turns, and check for oil buildup or other contaminates inside the Dawes causing slow reaction, it happens sometimes.

I've a 2001 zd30 di and my
Maf is dead. Anyone know the correct part number?????
Hi Mate, I have a late 2000 build and I'm sure the MAF is the same as yours, check it out anyway 22680-AD21A.
 
#24 ·
geeyoutoo,
Thanks for quick response, much appreciated.
I'm talking about drawings without vacuum solenoid. At your drawing I found that pipe to VNT going from tee which is between green damper and dawes device. At Chaz's drawing VNT connects to dawes device directly. So just want to undestand is there any principle difference..
I have boost bounce then I have high acceleration. No metter if I start from stop and griving at speed. *Boost goes to 17psi then drops to 8. And then recovers to 13-14psi. Sometimes it take from 2-4 sec so it's quite dangerows at road. Then i push pedal gentlly everything is ok.
I have dawes device from 3barracing, needle valve from cammozi. I disabled vacuum solenoid at all, blocked egr. I deleted the catalyst and the last resonator box. I have autometer boost and egt gauges. I dont have catch can, i just have pipe to atmospher. My IC is standard.
Then i implenented nads i tried to get reed of boost bounce by needle valve with no result. I had peak boost 21 psi. Than i ajusted VNT grub screw to 1/3 turn and it gave me 17 psi boost peak. tried 2 dawes devices and all the same. So recently I ordered hith load spring from 3barracing and waiting for it.
Your help and support are much appreciated.
Regards.
 
#26 ·
OK something you can try to soften that "bounce" I had this effect showing up on the dyno a few years ago with 8hp bumps in the graph, what I did was get a lawn mower fuel filter (with a little bit of size to it so it acts as a small reservoir) and fit it in the vacuum line as close to the VNT as possible, that fixed my problem. The HD spring will assist as it is definitely more positive, but make sure you read the HD spring sticky near the top of the ZD30 DI page, this outlines the trials I did and how to set it up as it is quite sensitive.

As GUEY says re the schematics, same result just a slightly different method.

Here is a pic of the fuel filter adaption.

Auto part Fuel line Hose Automotive fuel system Pipe
 
#25 · (Edited)
Same setup. GU2 has written green damper. Chaz has just written damper. Chaz has written actuator GU2 has VNT. Same drawing just drawn different.
Only other difference is GU2 has included vac cannister. Some vehicles have this and others don't.
I found GU2's easier to follow as it shows how to block vac soleniod and where to run the other side of the needle valve.
 

Attachments

#27 ·
Guey,
Thanks, i'm talking about those two drawings. Plese have a look at Chaz' drawing. VNT connecteed to tee which is partof dawes device.
Geeyoutoo drawing indicates that VNT connected to separate tee.
Regards
 
#30 ·
Thought I'd add this diagnostic doc to let people know what the ECU is looking at, this is a cut from the Electronic GU/GR Manual in the archives. I've added it to my personal drive.

diagnostic description ZD30DDTi.xps
 
#31 · (Edited)
Another addition, While I was modifying my air intake I removed the resonator and the vacuum solenoid, the ECU doesn't care about the vac solenoid switch so no codes were forthcoming. To do this I bought a 1/8"BSP pneumatic exhaust filter and screwed it into a 1/8"BSP x 3/16" barb fitting and this is attached to one side of the in cab needle valve and secured out of sight under the dash. So when you do the NADS with an in cab needle (which I would recommend) you only need to pull one line through the firewall grommet.

I have done a few NADS conversions using this method now, as sketch.

Diagram Auto part Automotive exterior Drawing Line art


BTW, when fitting a boost gauge and Dawes to a std intercooler, by far the easiest way is to fit an adapter to where the MAP sensor bolts to the front of the intercooler, they look like below and are available from Extreme Limits OffRoad and Off-Road Division (among others) and allow you to tap into a boost pickup point without other mods, very simple.

Boost Adapter.

Auto part Tool accessory
 
#32 · (Edited by Moderator)
Great thread G/u2

Just something also i would like to add if you don't mind G/u2, if you are new to patrols and have been driving for sometime then you find it suddenly down in power or lagging on the throttle,get the MAF sensor looked at and tested,do NOT continue to drive your patrol when down on power,this side of the globe here i know an extremly knowledgable patrol guy (he scraps and breaks them) constantly working on patrols,he said the most common cause of failure here was burned pistons from failing MAF sensors,even that is not the issue the main problem comes up because guys continue to drive when they are down on power!

When/if the MAF decides to pack it in your patrol will start to over fuel and burn the pistons up.
I guess i am one of the lucky ones,well over 300kmh's up now and on first day MAF,only thing i do in that area is clean my airfilter very often.


Check that MAF and remember it won't throw a fault code if it starts to act up,least this is what most people say!? but questionable G/u2?
 
#33 ·
Im still learning about all of this..
my boost on the highway goes up and down, yet no change in revs...
I believe the dawes setup will help fix this?

So you tune the dawes valve to max boost say 13psi...
what role does the needle valve actually have?

thanks.
 
#34 ·
Yes the Dawes will fix that as long as you bypass the ECU controlled vacuum solenoid located just below the MAF switch on the resonator box. The role of the Needle valve is to control the spoolup rate of the VNT after we have bypassed its normal control system which is the vacuum solenoid. If you already have experienced limp mode, setting it up this way will allow you to control limp through adjusting the outright boost (most vehicles will be able to get around 16psi but for someone new it is a good idea to start a little lower and work your way up once you are become familiar with it) and opening the needle valve to bleed a small amount of air into the system to reduce the vacuum being supplied to the VNT actuator, this can be somewhere between 1/4 to 1 1/2 turns open on the needle valve (open being turning the needle valve anti clockwise).

I recently NADS'd a 2005 which was jumping between 5psi and 20+psi cruising on a flat bit of road, we fitted the Dawes and Needle as described in the post #30 schematic, with the vent for the needle under the dash. Surprisingly we were able to get to 17psi still have the needle valve closed without limp, you can be lucky.

If you look in my signature in my channel I have some video's on the Dawes, one describes pulling a Dawes apart and how to adjust it.
 
#36 ·
ive watched a couple of them alread geeyou2! Very helpful..
So use the dawes to get max boost (around 13-14) and the needle is how fast boost comes on? Yes and Yes, remember the higher the boost the lower the EGT (within reason).

thats what your talking about running at 1500rpm 4-5psi then at 200 full boost?
thanks in advance! Yes again, remember these are starting out values, 5-6psi at 1500 and 10-12psi at 2000 are good start out settings. You can go higher as you learn more and modify more, I'm on 18.5psi now and that is achieved at 2100rpm
See answers in RED.
 
#38 ·
I buy this stuff direct from Darren Dawes in the US, he's a great guy and has looked after us well over the years (see 3bar link in first post) and it gets to us quite quickly, he also has a very good needle valve that I have tested
 
#40 ·
Sorry mate I've been off the radar for a while due to an accident, the little "surge tank" is purely a lawn mower fuel filter, many have no real "storage capacity" so just shop around until you find one that has a few CC of capacity.
 
#41 ·
vacuum

hey Geyou,
sorry to hear about your accident hope everything is going okay now!
:)

just wondering with the installation of the needle valve.. the vacuum line running to vcuum cannister then to tee piece...
im wondering if i have the right line... (the one ime using is the one in my hand in picture below.. but should i be using and bypassing one of the other lines circled in other picture??
thanks again!
Dan
 

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