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What are considered high and normal exhaust gas temps as sat on the motorway last night doing at 70-80 my temp was showing 800oC.
 

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it entirely depends on where the EGT probe is mounted. Which leads me to this question - where to mount it? I got into this with my tuner today - I thought mounting in the rear turbo elbow would be the best location, but he wants to put it much further back, near the end of the downpipe or even in the decat pipe.

Being that far away from the rear turbos (and exhaust gas from cylinders #4,5,6), will I get accurate enough readings to react fast enough if something starts to go wrong?

Where is the EGT probe mounted on stock BNR34s?
 

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What are considered high and normal exhaust gas temps as sat on the motorway last night doing at 70-80 my temp was showing 800oC.


If your cruising at those speeds the temps should be lower then that.........ideally 800-900 is probably the highest you wanna see when driving hard.

Best thing to do is get it booked in somewhere and get it checked......probably needs a few adjustments on the map.

Where are you located???

Harry
 

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Discussion Starter · #4 ·
I had though 800 was a little high, i'll have a look tonight to see which exhaust outlet the probe is mounted.

I'm in Berkhamsted, Herts
 

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Didn't know it was that hot!!!

BTW, Lamb, have you got a blue GTR & where you in North Watford last saturday? (around 1pm-ish)
 

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Cashpoint.....you have pm mate.


Didn't know it was that hot!!!

BTW, Lamb, have you got a blue GTR & where you in North Watford last saturday? (around 1pm-ish)

Yes i have got a Blue 34.....as seen in my little pic under my name.....but was'nt me out and about.......my car is off the road in hibernation for a while.
 

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ah ok thanks mate
:D
 

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800C pre-turbine is fine.

800C post turbine may or may not be fine.

EGT sensor anywhere other than 5-10cm from the exhaust valve is useless.
 

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800C pre-turbine is fine.

800C post turbine may or may not be fine.

EGT sensor anywhere other than 5-10cm from the exhaust valve is useless.
ergo, the best mounting location would be in the rear turbo elbow (as the rear runs hotter than the front)? That's more or less what I figured...sticking the probe in the decat pipe...how would that help me at all???
 

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`ergo, the best mounting location would be in the rear turbo elbow `

`EGT sensor anywhere other than 5-10cm from the exhaust valve is useless`

In case you`ve not figured it out, the elbow is AFTER the turbine.....

`sticking the probe in the decat pipe...how would that help me at all???` - Clearly it would not!!!!!
 

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oh really? I thought the turbo elbows were in the intake, after the intercooler, but before the air filter. Thank you for clarifying that.

Someone else suggested I stick the probe in the decat pipe. I thought that was crap, hence I brought up the topic in the first place.

I'll put mine in the rear turbo elbow, not in the manifold, and call it a day.
 

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Depends of course on what piston material you're using really I guess.
I'd agree 800celcius before turbo is a max on stock pistons.
There are EGT kits that run 6 individual EGT Probes that you can put in each of the exhaust manifold runners so you can record the temp of each cylinder.
The concerns of running before the turbo's is what if the probe breaks off and damages the turbine.
 

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exactly, which is why I will run post-turbine, but just barely after. As #6 is the lean cylinder, it's most likely the hottest, which is why I chose the rear over the front.

The Tomei elbows are so shiny and beautiful - pity to drill and weld a bung in one of them :p

oh, and the pistons I'm installing are HKS 87mm forged, with the nickel-plated tops that supposedly take higher temps. Not that I want to run higher, but more to increase the safety margin....
 

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Most Tuners who use a wide band lambda sensor put it in the decat pipe (after both exhausts have siamesed together). As already said narrowband o2 sensor and exhaust temp sensor should be in the turbo elbow (just after turbine).
 

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Chaps - you are quite a confused bunch.

Kismet-enginedestroyer....EGT - Exhaust Gas Temperature - nothing to do with intake side of the engine.

EGT probe needs to be in the EXHAUST manifold BETWEEN the cylinder head and the turbine to be off any use what so ever. Putting it in the elbow is USELESS.

I would be happy with 900-920C on std pistons, a bit more on forged items.

David - I suspect you comment relating to development engines is when auto running perhaps? Or as a safety margin so as not to damage $$$$ proto engine? 850C port temp on any new gasoline turbo is about 200C below the benchmark temp.
 

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Chaps - you are quite a confused bunch.

Kismet-enginedestroyer....EGT - Exhaust Gas Temperature - nothing to do with intake side of the engine.

EGT probe needs to be in the EXHAUST manifold BETWEEN the cylinder head and the turbine to be off any use what so ever. Putting it in the elbow is USELESS.

I would be happy with 900-920C on std pistons, a bit more on forged items.

David - I suspect you comment relating to development engines is when auto running perhaps? Or as a safety margin so as not to damage $$$$ proto engine? 850C port temp on any new gasoline turbo is about 200C below the benchmark temp.
You are right very expensive development engines

We arnt allowed to get near the point of melting them :chuckle:
 

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Chaps - you are quite a confused bunch.

Kismet-enginedestroyer....EGT - Exhaust Gas Temperature - nothing to do with intake side of the engine.

EGT probe needs to be in the EXHAUST manifold BETWEEN the cylinder head and the turbine to be off any use what so ever. Putting it in the elbow is USELESS.
apparently you can neither read nor understand subtle sarcasm. Tomei TURBO ELBOWS. They go BETWEEN the turbo and the downpipe. They're a good place to take EGT readings.:GrowUp:
 

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The problem with placing the probes in the elbows is the temp will drop too much by then. The idea of an egt gauge is to measure the temp inside the cylinders. Between the engine and the turbo, there will not be alot of temp drop. After the turbo, how will you know ???
 
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