Fitting boost gauge to 3 ltr td Patrol

Yes it was thanks Chaz. I even did a thread search on your name but never found it, so thought it couldn't have been you. We have had the EGT gauge fitted, now want to fit the boost gauge. Thanks so much for responding promptly. Motherhen

Hi Chaz, I was interested in this thread by your mention of a pillar pod and saw a photo on your website. Is this a custom made pod or are they available commercially? Certainly looks better than the vdo pod I have screwed to my A pillar.

gday chaz

I tapped into the same pipe as you, I would've prefered to go after the intercooler but its the only thick section to weld to. The only problem i see is that the pipe is before intercooler so the air temp is quite high. As a rule the turbo generates 7'c for every psi plus the ambient temp. So at 15psi on a 30'c day the air inside that pipe is 135'. I have an autometer gauge that came with nylon tubing....i hope it doesnt melt.
The max psi i have seen is 20 but thats only when i floor it on the highway & it instantly returns down to the 5-15psi range. With my faulty MAS it was recording 20-25psi constantly. what readings are you getting?

Warthog,
Those pillar pods are available from 4x4Megastores. I ordered mine from TJM in Adelaide and I think it came from 4x4Megastores warehouse in Sydney.
$125 and I had to cut the holes out and paint it, but I'm happy with the finished product.

Hi Goons,
I was also worried about fitting it there, but so far I've had no problems with it. I thought there may be a small pressure drop through the intercooler also, but I guess it doesn't really matter what your readings are, so long as you notice a rise or change in them when you have problems.
Mine too will peak at 20psi if I boot it, but with normal driving it rarely gets over 15psi. Looks like my readings are similar to yours.

Thanks Chaz.:-)

I am interested what temperature information you get Chaz from the EGT and MotherH too. I am intereted too in the pressures you are achieving Chaz. Do you have an altered turbo? I see the gauges at just over $30 and upwards on ebay and wonder the quality there, but the EGT gauges are all round $400. With a bigger exhaust I guess it is something I don't need to worry about as much anyway - the EGT that is.

Chaz, I have been told the pressure drop is about 2-3 psi on the engine side of the intercooler. I guess it is dependent on the cooling there but also the restriction through the intercooler. I asked a question on Outer Limits board as to whether the dump valve operation may be best operated from the engine side of the intercooler but could not even get anyone to think seriously about the problem.

You are certainly getting some variable pressures Goons, but I wondered the source of the 7 degree temperature rise. I found this article that is in Farenheit but it really does give a depth to the complexity of calculations and need for intercoolers. Turbo Saturns Actually there are quite a few interesting pages linked to this one on wastegates and the like.

Hi John,
I've only had the EGT gauge working for a few weeks, but it doesn't take long to see a pattern developing between driving style and temps. So far the highest temp I've read was 400deg.C and that was powering up a long hill at 90kph in third gear. Normal city driving, and it hovers between 200 when idling at the traffic lights to 350 when going up hills and accellerating away from intersections.
My pyro is about 50mm from the exhaust turbine so I'm happy with these readings because I've read that with this setup I shouldn't go over 530, but I'm keen to see what happens when I tow my CT.
My turbo is standard and pressures are normally between 0 and 10 or 12psi although I have seen 20. It seems to depend entirely on how far I push the pedal.
Strangely enough, I'm starting to see a rise in EGT's on cooler days. I'm not sure if this is normal, but it seems to be what is happening.

Over time I'm sure I'll learn a bit more and I think its a great way to keep an eye on whats happening and hopefully prevent any premature engine damage. For instance, I've now set my turbo timer to 2 minutes because thats how long it takes to come down to 200deg.

Cheers
Chaz

400 is still very cool... Mine gets upto 550, some ive seen have hit 600

normal is 10-12, and youve seen 20? something is wrong there.. sounds like the typical thing that happened with the 3.0GUs when donks blew up.

Hi Bruce,
Is your pyro is fitted after the turbo or into the manifold? I'm interested in a comparison, because I'm also considering that some heat is washed off in the water cooling of the turbo, and I can't remember if yours was standard. (Water cooled or not)
So far all the 3.0L owners with boost gauges that I have spoken to, including Navara drivers (4 people) have said 20psi is their max, but that is at full throttle.
I can't find anything in the manual to verify this, but considerind that the 3.0L is a relatively low compression motor, only 17:1 ratio, maybe 20 psi isn't all that high.
Cheers

Chaz,
Trucksters thermocouple is fitted in the dump pipe. I have 2 fitted on my 4.2TD since having the Denco turbo upgrade fitted. I have one in the manifold and one in the dump pipe and can switch between them to show the varying temps on the same gauge (a digital readout gauge; kit is from Thermoguard).
I have never had my manifold gauge hotter than 585oC and at that point the dump pipe is showing around 450oC. This new turbo is not water cooled, but I do have a 3" mandrel-bent straight through exhaust system which I believe keeps the temps down considerably.

Cheers

Roachie

Cheers Roachie,
That’s the sort of info I was after. So if you are showing a difference of 135deg, then a 200deg difference on a water cooled turbo wouldn’t be far off the mark.

I agree a larger dump and less restrictive exhaust could go a long way to keeping exhaust temps down and on that, I wonder if the 3.0’s catalytic converter could have any significant effect on exhaust temps. This is one area that hasn’t seen a lot of discussion among 3.0L owners and I was thinking of making up a dump pipe to replace the cat to see if there is any difference. Maybe a full 3” system with no mufflers and only a free flowing cat at the rear may be an option to improve the life of a 3.0L.

Chaz,
I wouldn't bank on there being any discernable difference in temps due the water-cooling of the turbo. I only recently had my water-cooled Nissan standard turbo removed and replaced by the larger Schwitzer "dry" turbo and there has been no noticeable change in any temps (either oil, water or EGTs). The water cooling must have been thought to be a waste of time on the 4.2TD, because the later model 4.2TDi have a "dry" turbo as well, so Nissan obviously had a change of heart about the benefits of water-cooling.
Cheers
Roachie

Chaz, I wonder the catalytic converter on the 3.0 litre you are talking of - is that on a diesel???

It seems a few of you guys are pitching for information and not sure what you need to do with it trying to decide that you need two points of measuring the EGT. My dump pipe is drilled and tapped for an EGT but I won't put one in unless I know I can get useful information.

I see you are all talking boost pressures but wouldn't the useful boost be after the intercooler and if that the case, also the air charge tempreature too? That would also tell you the efficiency of the intercooler if you also had the pre-intercooler temperature too. Make it a real research test bed.

By the way, this is a far more sensible discussion than I was able to get out of Outer Limits forum but there is a need to understand what we are all seeking to know. There is a lot of impure research here and it doesn't cure the need to know, but I am troubled it isn't telling heaps either comparitively speaking either.

I would like to know how I can improve reliability - not that the engine reliability has been a problem, but improve the tangeable preformance - fuel efficiency and know the steps to achieve the performance with my vehicle. The order to achieve and that sort of thing too do first. Interested in your comments guys.

Hi John,
Yes, the Patrol 3.0Di diesel does have a catalytic converter, and it is the dump pipe.
This is why I have a concern regarding the restriction in the converter and its effect on backpressure and EGT’s. Most of us (Nissan 3.0Di owners) on this forum have genuine concerns about the reliability of these motors knowing their past history.
So we need to know what conditions are normal and from those who have had problems, what they had experienced as abnormal.
I guess fitting a gauge doesn’t mean much unless you have some idea of what your reading, but just noticing a change could be very helpful.
I agree that the boost gauge should be terminated at the cool end of the intercooler, but at the time I fitted mine, I was more interested in what the turbo was producing and that it would be reading a higher pressure at this point.
Regards

Chaz

Chaz, thanks for the info about the catalytic converter on the 3.0l. I thought those things were limited to petrols so better refer to the manual I guess. Bruce, Roachie and myself all have 4.2 Nissans so I guess have different needs to know things to some extent.

I reckon I would know what I am reading with a boost gauge but need to know comparative readings too. I have been discussing intercooler sizes with Bruce as I wonder at the size of the one on mine being the same as on the 2.8 a few years ago. In other words, does it reduce the charge into the engine. Cooler, yes to some extent, but also I have been told reduce the pressure by 2-3 psi.

With the 3.0 I also guess that there is some compendation providing additional fuel if your oxygen sensor knows there is additional boost air going through - if it peaks as high as you say you observe. I think some of the diesel tuners actually tune 4.2 diesel motors on the level of fuel/air in the exhaust rather than a dyno. I heard that asking MTQ about the tuning.

Thanks again Chaz,

John R said: " trying to decide that you need two points of measuring the EGT".

I feel I should explain how I came to have 2 EGT thermocouples.....
Originally, when I first decided to fit the EGT gauge, I took Ian's advice (Thermoguard Instruments) that the best place to measure EGT is in the manifold. So I went to a mechanic and had them unbolt the turbo, slide a piece of cardboard in between the manifold and the turbo (to prevent any swarf gettinng into turbo) and they drilled and tapped the required hole to fit the thermocouple. That system worked quite okay and still does. The 3" exhaust I had fitted at that time utilised a custom made dump pipe from Binskins, but it didn't have a lug for the thermocouple, otherwise despite Ian's suggestion, I would have opted for the thermocouple to be located in the dump pipe.
More recently, having the new turbo fitted, which has a new dump pipe complete with lug, I decided I may as well fit the extra thermocouple and a switch on the back of the gauge itself, so I could see exactly what the temp difference is. From what I can gather, I am the only bloke who has done this on this forum and it simply confirms that there is a difference of up to 150oC between the manifold and dump pipe when the donk is working hard.
Cheers
Roachie

My mate just got an air/fliud intercooler for his 80 series it comes with its own small radiator and electric fan . This would solve this problem as it doesnt rely on motion only to provide airflow for cooling.

I dont know if they make one for a Patrol .

Glenn.

G'day Glenn,
Yes Denco do make a kit (liquid/air) intercooler for the Patrol (4.2GU) but on the advice of their agent in SA who fitted my new Denco turbo upgrade, I decided it wasn't worth the $1815- plus labour.
However, I'd be interested to see what your mate's findings are once he has fitted it up.....does he have EGT and oost gauges in already, as it'd be nice to know whether he experiences temp drops etc.
Cheers
Roachie

Goons, reading the article that I referred to actaully could provide similar figures. I really wonder the adequacy of the intercooler provided as standard for our conditions. I wonder the cooling versus the restriction that is built in. When you consider the original cost plus a replacement, it is a bit like the inadequate dump pipe off the turbo. How come Nissan didn't.............. It could have made a considerable difference.

I guess having fitted a new mandrel bent from the turbo and measuring the difference I ask more questions of my piece of gear. Goons I also ask if you have a standard turbo and what it is fitted to. If it was an old mechanical pump like mine, and Roachies for that matter, you would need to boost fuel as well as the boost rate.

Thanks in anticipation.......

He doesnt have any gauges fitted , I know thats close to blasphemy on this site , but rekoned it went heaps better .

Going from no intercooler to a decent one would be fairly noticable. I wonder if you could tell the difference between the stock one and an aftermarket one ??.

Glenn I don't have any extra gauges fitted on the engine side at the moment either but do wonder about a better performance from a bigger intercooler than the tiddler on the 4.2 GU that is standard - the question you ask. I have seen some available at reasonable cost too seeing I already have the pipework.

I reckon I wil have to get a boost gauge before too long Bill. Did you get a fuel pump adjustment after the boost lift?

G'day John,
Yes mate, they tweaked the fuel pump up a tad and the boost max's out out about 14.5psi (although I rarely allow it to go that high under most conditions).
Cheers
Roachie

Bill, when you say you seldom let it reach that, do you have a boost adjustment? Was the tweaking of the pump on exhaust fuel/air mix or on a dyno?

John,
No, I just use throttle control to limit the boost amount to about 12psi under most circumstances. In other words, under acceleration, I keep one eye on the boost gauge and try not to let it get above 12psi.
Cheers
Roachie

John,
sorry, I missed the 2nd part of your question. Berri Diesel doesn't have access to a dyno, so the fuel was adjusted manually and the egt's and boost pressures were all "matched-up".
Cheers
Roachie

Hi Chaz - Ours is fitted 'in the hottest spot'. I am looking for the readings we took when towing (without a load in van or car), but can't find them. We took note of the temperature reading and revs of vehicle, and whether cool (in the morning) or warm (in the afternoon). They are not lost - i just don't know where they are. Today we went to Bunbury shopping, and on the way home it was getting up to 400 degrees, but the last hill put it up to 500 degrees. Weather was mild to warm. We purchased a gauge, and will nail down son to help us put the boost gauge in before he goes back up after his holiday. May ask you a few questions then if OK with you. Thanks, Motherhen

Motherhen,
Thanks, I was just courious how much it went up when towing. I'll get a chance next month when I tow my C/T up into the Gawler Ranges with a hefty load. Yours is running nice and cool.
Good luck getting the boost gauge in, and feel free to ask anything, anytime.

Cheers
Chaz

Darn, when i submitted a reply, i got an error message and lost it!

Thanks Chaz. From memory, i don't think it has ever gone much over 550, with or without caravan, but have only taken the caravan on one drive and without a load in it or the car since fitting the gauge. Some hills on the run but nothing extreme. Caravan is 2.2t tare on lic papers, so with water and luggage i shudder to think of the weight.

Watch this thread and i will post the temps if i find my notes. We'll see how it goes in Tasmania, with a load and the mountains. I'll report to the forum when we get back.

From reports on the forum, it appears we should get the mass airflow sensor changed every 100,000 kms. Ours has just clicked over 1g, so will be looking at changing it before going to Tassie, regardless of the boost readings. Any idea of the cost?

Regards, Motherhen

Motherhen,
Recently on "That Other Forum" some body posted that Nissan had brought out a "new improved" MAF sensor for the 3.0Di. I think he mentioned that it was the same one as used on the 350Z and around $250. This hasn't been verified, but if it is the case, I'm thinking of carrying a spare.
Creiky, what am I doing up so late!

Chaz

g'day chaz
on my 3.0ltd navara the egt gauge is fitted in the exhaust manifold before the turbo the highest reading i've had towing the van is 650c,i;ve also had that reading giveing it heaps up the moonbie range, with out the van hope this helps
cheers toohey