EGT questions

Nero

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Drove my truck into work today after finally getting it mostly sorted out.

I have no load, bed empty cab empty.

Going up slight inclines maintaining 65mph my egts creep up to 900f and sit there until I get back on flat ground, then drops to 500 ish.

How in the heck am I gonna manage egt's with a load behind me?

For info, my egt probe is in the drivers side manifold between the rear two cylinders.

I'm intercooled.

Only thing I can think of is because I still have the stock exhaust causing a mild restriction.

Thoughts?
 
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Nero

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Doing some google fu, I wonder if I just need to change my driving style. Reading where some guys drop it out of 5th to keep rpms up around 2800 and that lowers egts but maintains speeds.

Hmm...
 

Old Goat

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5th being OD, the incline will make the Engine work harder even if it is still pulling good and maintaining speed.
As you said, drop her down a gear.
Intercooler give you a more dense air and may cause it to burn hotter.
Just some thoughts.

I have read 3" pipe makes it flow better, anything bigger is bragging rights, doesn`t help much.
What`s stock? 2 1/2".


Goat
 

Clb

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Closer to 3k the better.
Hit the bottom of the hill spooled up where you can still accelerate but not on redline.
2 stroke made mine run hot.
So additives or maybe wmo could be something to look at.

For grins....
I've not seen a thread on testing thermocouples (probes) but Boiling h20o @210 should be a good check
 

THSIM9

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Doing some google fu, I wonder if I just need to change my driving style. Reading where some guys drop it out of 5th to keep rpms up around 2800 and that lowers egts but maintains speeds.

Hmm...
This is what I have done with my previous setup. (Banks sidewinder, no intercooler, stock ip and injectors) if I drop to 4th or even 3rd and stay at the higher RPMs I see lower EGT’s while pulling grades for sure.
 

Nero

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Good to know.
I'll be dailying my truck for a while to make sure its good to go for camping season, I'll just have to shift differently.
Thanks for the feedback everyone
 

KansasIDI

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Good to know.
I'll be dailying my truck for a while to make sure its good to go for camping season, I'll just have to shift differently.
Thanks for the feedback everyone
Hell I hit 1000 empty up hills all the time… loaded with 10k it really doesn’t get much worse, 1200 max, if I downshift to go up a hill then it usually stays at 1100 or so
 

FrozenMerc

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As Kansas was getting at, where do the EGT's stabilize? Thermocouples react slowly and normally take longer than a quick blast up a hill to stabilize. My thermocouple is right behind #8 exhaust port, just in front of the manifold flange. It is damn near impossible to get the EGT's over 650 empty, but they will sit at 950 all day with the big enclosed behind it. I am running a small, stock pump, so we will see what happens when the new CDD pump arrives....

You may want to invest in a quality Wide Band A/F meter and install that as well. 14.5:1 is stoich with a diesel, and anything below that (fuel rich) will cause the EGT's to start climbing. I use A/F gauges on all my carbureted gasoline stuff, and it really helps to dial in performance and efficiency while making sure I don't get into a bad lean or rich region.
 
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Cubey

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The lower the RPM, the higher the EGT because it's under a heavier load trying to maintain speed, with less airflow going into the engine. Engine temperature will rise the more you downshift to keep EGT under control.

The RV would get down to 1st gear on very steep grades at 20-25mph near the top, in order to keep EGT around 1000-1100 maximum. Engine temperature would creep up around 220-230 depending on the daily temperature, wind, etc.
 

IDIBRONCO

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Only thing I can think of is because I still have the stock exhaust causing a mild restriction.

Thoughts?
If you have any doubts, you could always cut the exhaust in front of the muffler and drive it for a couple of days to see what that does. If it does nothing, you can always use one of the slip over types of clamps and clamp it back together.
 

Nero

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I did some experimenting on my way home.
Every day I drive up a hill that has about a 6.5 average gradient for almost 3 miles.

In 4th I averaged 700f at 55mph, in 5th same speed it jumped up to 950f.

Guess I get to learn how to drive my truck again.
 

Lumberjackchuck

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Dang, unloaded with a 110 cc pump I have trouble getting EGTs up to 700. I really have to push the throttle all the way to floor going up hill accelerating to get that high.

I am also 4” straight piped + 3” down pipe on the exhaust and Intercooled.

I would definitely start with upgrading your exhaust. Seems kinda high for unloaded.
 

Nero

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@Lumberjackchuck where did you get your pipes? I thought about getting something bigger but don't want to break the bank. Technically I'm out of funds for the truck project, I had only saved up enough for the pump, injectors, intercooler and head work.
 

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