where to plumb boost gauge

[kiwinoz]

I've seen ( on the web) turbo boost gauges plumbed into the pipe between the turbo and wastegate actuator. And heard of them being plumbed into the line from the manifold to the fuel injector boost compensator.

Where is the best place?

And if the best place is off the manifold, can I later add a boost controller to the turbo/wastegate?


Thanks
Turbo Diesel Nubee

[keepwalkn]

What engine?
TD27T - Best place is from the boost port on the back of the turbo cross over pipe.
It is a 1/8th NPT thread. You can get a T piece that screws into the boost port and have 6mm nipples on either side of the T. One side to the boost compensator and one side to your boost gauge.

TD42T - I recommend removing the intake elbow on top of the intake manifold and have it drilled and tapped with a 1/8th NPT thread. Then purchase the fittings to suit
See here:
http://www.patrol4x4.com/forum/nissan-p ... 42t-31784/

[mumbls]

hi tubro diseasel nubee
i think the best place to plumb in for serious plumbing and lots of plumboost is in the waste gap sensor on the rear fiddle breaks bias valve, youll know when you hti serious booost levells with it in there, just cable tie it on.
no sweat my bro

[kiwinoz]

oops TD27T

and i think i have found the rear fiddle breaks bias valve, but do i want pos or neg bias ?

Thanks Keepwalking

[keepwalkn]

Couple of images for everyone playing at home.
One Is the factory location to source boost from with a T
One is where I tapped the intake elbow and fitted the T

[kiwinoz]

Just wondering why there and not the orginal place?

I see you have removed the butterfly valve too, did you do away with all the piping to there and the EGR valve?

[kiwinoz]

And.... Im guessing mumbis was having a bad day, but I often see comments from people who feel they just have to comment, even if the comment is of no help.

[hamboy]

I have mine plumed in on the wastegate actuator line, i find it more acurate. its probily better on the turbo as they tend to go bang before the motor on high boost

[Crash bandicoot]

The most accurate place to have a boost gauge is on the intake manifold. this then accounts for lost pressure and resistance from piping and the intercooler and gives you a true reading of how much pressure drop there is between the turbo charger and the inlet ports. this is also the more accurate place when tuning the engine/ injector pump as it may read 15 psi at the turbo housing but only 11 or 12 psi at the intake manifold.

[mumbls]

And.... Im guessing mumbis was having a bad day, but I often see comments from people who feel they just have to comment, even if the comment is of no help.

Apologies, I thought you were a troll,


Maybe I misinterpreted

The best place to for a boost gauge is the place you want to measure
Do you know what you want to measure?

If you want to monitor intake manifold pressure T off there
If you want to monitor turbo housing pressure T off there
etc etc etc etc

I dont believe there would be a large [1psi] difference in a variations from housing to intake manifold in a non intercooled engine like yours

You answered all your own questions. Just dont buy a $12 ebay item, if in doubt use someone elses gauge an compare. I'd recommend a Auber instruments gauge, and digital sendor.

[kiwinoz]

Troll ? i don't think you mean under the bridge type, so, is this some internet slang?

Anyway, my next question was going to be about pyro sensor placement. Seems to be quite a variation in temp prior to turbo compared to dump pipe (or EGR blank), understandable tho, but when someone quotes EGT is it normal to also state where the sensor is located? If not, maybe it should be.

(Bit like saying 650Ks from a tank of fuel....what size tank)

Hmmm.... and now it's asked.

[mumbls]

nah no troll, ROLL BREAD?

Are you really going to go and drill / weld a nut on where I tell you to?\
If so, put in your snorkel, for max plumb boost, or just tap it into your spacegate for effortless boost.

If not tap into your ex manifold preturbz for max turbz exigast temps

Want me to show you a picture of my egt gauge to confirm I know what im on about an that im all shit?

[kiwinoz]

no thanks, forget it.

[mumbls]

sorry OP maybe pictures will help explain

here's where I put my EGT probe
I feel it gives good electrical gas testing around my visibly leaking battery [dangerous hydro sulphides] and also close enough to my DIY coke bottle catch [or miss] can.

can't have to much electrical gas under the bonnet. I also recommend cutting a hole in the bonnet incase there is to much egt, shown here




also this is where I plumbed up boost T - into the dash!
im not sure why i have two, i think one for high boost one for low boost.


hope this helps OP

[The Stranger]

Anyway, my next question was going to be about pyro sensor placement. Seems to be quite a variation in temp prior to turbo compared to dump pipe (or EGR blank), understandable tho, but when someone quotes EGT is it normal to also state where the sensor is located? If not, maybe it should be.

We know a few things, and some we can guess.
1) Auminium and it's alloys (pistons) melt at about 660c.
2) Std TD27 will hit 700c with the probe installed just pre turbo.
3) GM say 710c is fine for extended periods, and up to 760c for up to 5 minutes - but that's GM, not Nissan.
4) I've hit 820c on several occasions (before installing IC and water injection) and the engine seems none the worse for it.

We don't know exatcly how much drop in temp there will be across the turbo - estimates vary.

It occurs to me that post turbo means you are going to have to err on the safe side so you are better to go pre turbo. On the TD27 there is a convenient heat sheild bolt hole right in front of the turbo inlet that can be drilled and tapped for the probe. This is where mine is.
I drilled and tapped mine with the turbo and manifold in place. Though this can not be recommended as there is an element of risk, with the engine running the swarf wants to blow up and out of the hole (wear safety goggles).

So while none of that give you a definitive answer it hopefully gives you a guide. I went for 700c max (so not exceeding std) on full load (towing boat up a hill on WOT). Round town sans the boat it doesn't exceed 600c

[1hamish1]

I have my egt gauge pre turbo (td42t) and stick to 700max and thats really working hard foot flat in it on hills.

[keepwalkn]

150 to 200 degree drop across turbo...
I will be going post turbo on my TD27 and aiming at 550 degrees.