EGT Gauges

[Uys]

EGT Gauges - do you use them, and which one? Where did you fit the probe? Looking for one with a small display to fit without drilling or cutting holes in the dash.

Any experience with this one?


http://www.dynotunenitrous.com/store/scripts/prodView.asp?idproduct=134

 

[dsw4x4]

Before buy just a egt guage consider this if your going to do anyother performance mod to your motor most "chips" come with a egt gauge and alarm so if you spend 200 for a gauge you could have a whole lot more for for another 2 or 3 hundred dollars you can have shift point, fuel, boost, speedo control and a lot more depending on the chip. Just something to think about.
Derek

 

[ntsqd]

The point in the exhaust stream that is important to a turbo (I'm assuming that we're talking some sort of turbocharged diesel engine) is right above the entry into the turbo. That is where you want to measure the EGT. The temperature of the gases flowing across the turbine wheel is the biggest concern. Go too hot and you damage the turbo or the engine. Measuring the temperature downstream of the turbo is handy for engine development work as it can tell you part of how well the turbo is performing, but is it nearly worthless for protecting the turbo from over temperatures as the temperature drop across each engine/turbo combination is unique.

At work we use 900*C type K thermocouples from Omega.com for this measurement. Most of the commercial EGT gauges that I've seen used this same t-couple buried under some proprietary packaging.

 

[Christian]

The point in the exhaust stream that is important to a turbo is right above the entry into the turbo.

Not that I in any way disregard what you are saying, but I have just bought an EGT meter from one of the most reputable (if the most reputable) instrument companies, namely VDO. And in the installation guide it is pointed out that the probe should be mounted post-turbo?

 

[R_Lefebvre]

I use an Autometer full sweep digital pointer gauge. It's easier to read when doing a quick guage check. The probe is right before the turbo which is where it needs to be. Putting it on a single manifold runner is not optimal.

 

[R_Lefebvre]

Not that I in any way disregard what you are saying, but I have just bought an EGT meter from one of the most reputable (if the most reputable) instrument companies, namely VDO. And in the installation guide it is pointed out that the probe should be mounted post-turbo?

Well, that's just crap then. I have to imagine that it must be because VDO's probe can't take the heat, or they are just covering their assets against the possibility of the sensor probe breaking off and damaging the turbo.

Either way, it speaks to VDO's quality, and not anything to do with good engine management practice. An EGT after a turbo is fairly pointless.

 

[benjamin]

I use an Autometer full sweep digital pointer gauge. It's easier to read when doing a quick guage check. The probe is right before the turbo which is where it needs to be. Putting it on a single manifold runner is not optimal.

X2...Pre turbo is the most accurate location.
You want to know what your cylinder temps are so you don't melt the pistons. All of Banks turbo systems (at least what I've installed) are pre turbo, abt. 2 inches downsteam.

Dennis

 

[IdaSHO]

Another vote for pre-turbo.

That is where mine is on my Powerstroke.

And it is, after-all, reading the temps that the turbo is seeing. Post turbo temps are considerably less.

 

[wanderer-rrorc]

they are supposed to go as CLOSE to the exaust ports as possible..pre-turbo better!!.mines tapped into the driver exhaust manifold...

I use this one...nice and tight..easy to read...and cheap..bout the size of a pager..

http://auberins.com/index.php?main_page=product_info&products_id=19

thermocouple sensor...
http://www.auberins.com/index.php?m...s_id=2&zenid=6e6d5aa214914d4652e4ed6405abdd7f

 

[chasespeed]

I have seen mfrs suggest POST turbo mounting, and, after speaking with a tech rep, its a liability thing. No one wants to buy a turbo for a customer who installed a probe wrong, and blame the company.

As far as MFRs I have used...in order of preference for Pyros..

DiPricol
Isspro
Autometer
VDO

The DiPricol, and Isspro have the best response as far as a Pyrometer, at least IMHO. The autometer was good, but, seemed a little slow...but, for the record, the one I installed on my buddies car, seemed to react faster... so.. take what you will...

And I wasnt happy with the VDO...

Anyway, IF you have a turbo diesel, mount it PRE TURBO, in the manifold, before the turbo mounting flange. If its a V6 or V8 diesel, in the easiest to access manifold, before the flange.

You want to monitor EGTs for 2 things, first, being engine damage, 2nd, turbo damage.

I have seen several apps with pre and post turbo pyros, and the difference is interesting...

Chase

 

[Christian]

Well I've done some research on the preferred location on IH8MUD amongst other places. Let me stress that I mean preferred, not necessarily the right location. The reason I put it that way is by no means to discard the merits and knowlegde of the sources, or those of you who have written the same here, just to stress that I do not posses the knowledge to determine who are correct. Most prefer pre-turbo for the reasons listed above, but some, with equally good merits state that post-turbo is what they prefer.
To sum up what I have read I will list the pros for each location:

Pre-turbo:
More precise readings
Faster response to changes
Better when tuning as you can go closer to the edge

Post-turbo:
Easier installation
Less risk
just as good when what you want is an indicator of engine operations

As all others have listed the arguments for pre-turbo, I will list some of the argument for post-turbo installation:
All major truck manufacturers install post-turbo.
The EGT is not a precise measurement of engine performance, and should therefore be used as an indicator only, hence post-turbo is just as good, of course a lower threshold is accuired (around 1100F or 600C).
As you do not have information on what is the correct EGT form the engine manufacturer it is opointless to use it as a precise instrument.

Since I have no plans of pushing my 1KZ-T anywhere near any edge, I will use the post-turbo location. I have faith in what VDO recommends, and faith in the product. For me the EGT-meter is an indicator which I will use to warn me if I push the engine to much, say going up major hills etc.
But I can fully understand the arguments for pre-turbo, and why so many of you prefer it.

 

[chasespeed]

With todays thermocouples, I dont see any significant risk of damage to the turbo.

Having seen engines with pre AND post turbo pyros... a post turbo pyro is about useless. The turbo adds a dynamic to the equation. The only thing a post turbo pyro is good for, is shut down, as its a much better indicator of turbo heat. They hold heat... period.

You magic number is about 1250* You can run all day at 1200*..... the higher that number climbs... the less time you can run it....

And to be honest, its pretty easy to drill into the manifolf, and tap it.....

A trick I learned... and it works...

let the truck be cold.... get your drill, tap, and cutting oil ready....

Use a punch, and punch your location...

Start the truck....

Drill your hole, USING eye protection... the shavings will blow back in your face....

Oil the tap, and hole, and start tapping... the same thing.....might even add a little throttle....

Shut'er down, and install the fitting, and viola....

I have not seen or heard of a thermocouple in the last few years, breaking off.... quality parts, are just that....

BTW, 1100 post turbo, isnt a good number.... too high...

Good luck...
Chase

 

[Bella PSD]

I agree, Pre turbo 100%!

 

[ntsqd]

The problem with post turbo is that you can not expect the temperature drop across the turbo to be consistent. It will vary with how hard the turbo is working.

Said another way, the turbo uses heat to spin the turbine wheel. The more heat that it has to work with, the harder it spins the turbine wheel. The harder the turbine wheel is being spun, the larger the temperature drop that there is across the turbine side of the turbocharger. At a specific loading and engine rpm you might be able to know that there is a 200* temperature drop, but alter any of the variables and you no longer can say with certainty that there will still be a 200* temperature drop. Therefor after turbo tells you nearly nothing about how hard the engine is working because the temperature drop across the turbine wheel is not consistent.

We've had standard thermocouples up a little past their 900*C limit. No problems with FOD to the turbine wheel though the t-couple sometimes doesn't work all that well any more....
None of the arguments for post turbo have any merit.

 

[Christian]

Ok ok ok! enough already!!! I'll see if I can get it mounted pre turbo then [sulking]
I hate peer pressure!:jump::jump::jump::jump::jump:
But if everybody else is jumping, I'll jump too!