Egt

[blackdsm91]

Best spot for egt probe on a 2g?

[sbiggi]

Pretty sure its the number 2 runner, 6 inches off the head.

[mitchel63]

I would put it on the number 1 runner, about 4" away from the head.

[blackdsm91]

Ok, so we have two different answers....anyone else...?

[Bryan Savage]

I'll go with the number three runner, 7.1385 centimeters from the third-from-the-left manifold stud, measured from the fourth thread down, on the mean diameter line.

Using my finite element analysis fluids program I wrote, this is the spot that will provide the clearest readings. Don't screw it up!


























*THIS POST IS CRAP. DO NOT TAKE ME SERIOUSLY*

[intaginize]

Number 1 runner, 3" from the head, or number 2 3" from head. :) it's on the number one on my 1G, but that manifold has been on my car since 2000. All the old School DSM'ers used to use the number 1 runner, not sure if that's still holds true. :)

[v413nc3]

The number 1 runner is theoretically the leanest. Put it far enough down from the head so that the probe sees limited flame from unburned fuel (almost moot in our case) and far enough down that it clears your studs or you won't be able to put the manifold on. Let's all stop with the conjecture and actually give a damn reason why it should be placed somewhere.

[blackdsm91]

The number 1 runner is theoretically the leanest. Put it far enough down from the head so that the probe sees limited flame from unburned fuel (almost moot in our case) and far enough down that it clears your studs or you won't be able to put the manifold on. Let's all stop with the conjecture and actually give a damn reason why it should be placed somewhere.


Thank you.

[95TSIAWD]

I would say on the number 2. The reason being, the cylinders in the middle normally run a little bit hotter, granted the number 1 may run leaner, the number 2 is not far off.

[v413nc3]

That small amount of temp difference won't make up for the leaner condition of the last cyl to get gas. EGT's raise more with a lean/rich condition than they will with an engine heat difference. ~5-15*F won't make much difference on combustion temps.

[Mirage]

I'm not going to go too far in depth with an answer, but here's what's worked for me.

#1 cylinder as close to the exhaust port as possible.

Reason 1

You want to know how hot the gasses are at the valves and piston top, correct? So why would you put it in the collector or further away from the port?

Reason 2

It's been proven numerous times that #1 fails sooner due to heat, or mixture related issues for numerous reasons. #2 is a close runner up, but it's still second in line for failures.

Mine personally has been in the #1 runner about 2" from the cylinder head for the past 7 years. I have recorded several runs with 1700-1800* temps at that spot.

Marcus

[blackdsm91]

I'm not going to go too far in depth with an answer, but here's what's worked for me.

#1 cylinder as close to the exhaust port as possible.

Reason 1

You want to know how hot the gasses are at the valves and piston top, correct? So why would you put it in the collector or further away from the port?

Reason 2

It's been proven numerous times that #1 fails sooner due to heat, or mixture related issues for numerous reasons. #2 is a close runner up, but it's still second in line for failures.

Mine personally has been in the #1 runner about 2" from the cylinder head for the past 7 years. I have recorded several runs with 1700-1800* temps at that spot.

Marcus


Damn :eek:

[mitchel63]

My post above wasn't actually me....my friend was on my computer.

I'm with Marcus. Mine is in the number runner about an inch and a half from the head.

[v413nc3]

Too close and you can get errant readings from unburned fuel.

[blackdsm91]

Too close and you can get errant readings from unburned fuel.


That's what I thought....readings would be crazy...would have to get a pretty high gauge too...

[mitchel63]

Too close and you can get errant readings from unburned fuel.


It's not like I ever look at it anyway!

[blackdsm91]

It's not like I ever look at it anyway!


lol :confused: :confused:

[nefkntym]

Marcus, if you recording 1700-1800 degrees max per run. What is your average sustained EGT when you are cruising around, operational dsm permiting? Say around 3800-4000 rpms?

[blackdsm91]

Marcus, if you recording 1700-1800 degrees max per run. What is your average sustained EGT when you are cruising around, operational dsm permiting? Say around 3800-4000 rpms?


And what kind of gauge are you using??

[nefkntym]

I am using a Westach egt gauge and a TRE probe.

[Mirage]

When it's running, I usually see around 1400* cruising temps.

I typically don't even look at that anymore. I typically only tune for knock anymore.

I don't see 1700+ all the time, I've only noticed it a couple of times with a massive boost leak present.

I'm using an Autometer 0-1600* gauge. The 1700-1800* is estimated judging by how much further the gauge goes beyond the scale.

Marcus

[nefkntym]

When it's running, I usually see around 1400* cruising temps.

I typically don't even look at that anymore. I typically only tune for knock anymore.

I don't see 1700+ all the time, I've only noticed it a couple of times with a massive boost leak present.

I'm using an Autometer 0-1600* gauge. The 1700-1800* is estimated judging by how much further the gauge goes beyond the scale.

Marcus

Thats what I figured, when I am cruising around, operational dsm permiting, its usually around 800-850 C. Which I think is kind of high.

I think my timing is off. I come home in about a week, so I will get a chance to check it and redo it regardless since I have to replace the waterpump.

My guage is 0-900 C.

[v413nc3]

Yeah, that massive boost leak causes a rich condition then your probe gets hit by flame instead of exhaust gas. Since a flame is hotter than exhaust gas it is going to go way off the scale.

[nefkntym]

Yeah, that massive boost leak causes a rich condition then your probe gets hit by flame instead of exhaust gas. Since a flame is hotter than exhaust gas it is going to go way off the scale.

What's up Jake...

I wouldn't doubt it, since I did that new setup with that Calsonic R34 intercooler. I never did get a chance to check for leaks before I came back. Yet another thing to do.

[blackdsm91]

Thats what I figured, when I am cruising around, operational dsm permiting, its usually around 800-850 C. Which I think is kind of high.

I think my timing is off. I come home in about a week, so I will get a chance to check it and redo it regardless since I have to replace the waterpump.

My guage is 0-900 C.

That's what I thought...it should be well under 1000 degrees. Where is your probe installed?

[nefkntym]

Number 1 runner about 4" (http://studio1027.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=556&g2_serialNumber=1) down stream from the flange.

[blackdsm91]

Number 1 runner about 4" (http://studio1027.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=556&g2_serialNumber=1) down stream from the flange.

cool...think that's what i'm going to go with or close to it.


btw, how's iraq treating you? Al Taqaddum - where is that? I was in victory by the airport.

[nefkntym]

Its hot and sandy. TQ sucks goat nuts.

I was at Slayer for 2.5 years before coming out to west iraq. Where were you, striker?

That is good place to put the probe. From what I understand you always put the egt probe in the #1 runner to measure heat to issues relating to lack of fuel, fuel system. Later, in the mods and the peformance you put the probe or a second probe in the #2 runner because, the #2 cylinder apparently gets less air due to intake manifold design and such.

Jake or Marcus would be able to better expand on this if needed. This was just a simple placement thread so it probably wouldn't be needed.

Please correct me if I am way off.

[blackdsm91]

Its hot and sandy. TQ sucks goat nuts.

I was at Slayer for 2.5 years before coming out to west iraq. Where were you, striker?

That is good place to put the probe. From what I understand you always put the egt probe in the #1 runner to measure heat to issues relating to lack of fuel, fuel system. Later, in the mods and the peformance you put the probe or a second probe in the #2 runner because, the #2 cylinder apparently gets less air due to intake manifold design and such.

Jake or Marcus would be able to better expand on this if needed. This was just a simple placement thread so it probably wouldn't be needed.

Please correct me if I am way off.


I was close to slayer and striker - I was at striker before we left. But the whole time I was at victory north or was it south....don't remember, they kept changing the names there...its probably changed again now. It was where the division (1cav) was at.

[blackdsm91]

By the way, you need anything out there? When you coming back? You stationed in Carson?