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I have hauled some heavy loads over the last hay season and I think my miss guidence from other people have swayed my beter judgement on EGT. Loaded or unloaded I dont exceed 1200*. I had 2 1600* mishaps unloded. I know that people will say that 1500* for a few seconds is ok and others say don't go over 1000 hauling heavy loads. What I would like to know is 3 figures..Unloaded sustained temp*Unloaded Max few second bursts*Sustained loaded temp*I wont hold you to the temp but I am curious on what people are running. This is all pre-turbo readings.

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Well I am in the 1200 max temp school of thought as well. However, I have also learned that 1300 is seeming just as fine. Truck wont hit 1200 empty wot. Usually levels around 1100, andbut the time that happens, I am too worried about johnny officer at those speeds. :whistle:When I am loaded I let it climb to no more than the 1250-1300 range. However only if I am just about at the top of the hill. Usually a decent hill in overdrive and kinda wanna hear the turbo and clean the carbon out. However on the steeper hills I drop to a gear, (manual downshift the auto) where it runs about 2k-2100 rpms at half peadl. EGT's usually hover around 900 then. I wouldnt want to keep it under a heavy load for a long time at high egt's.

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I have been running 1200* at 18k lbs up 6%+ grades. I'm thinking that my numbers are too hot for sustained periods that hot.

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Aluminium melts at about 1250*, yet the pistons are an alloy, so they can go higher. So, sustained temps of 1200* are ok.I am in the school of 1250* or less for sustained durations.When empty at about 75 mph, my egt's are about 800*'s. Unloaded sustained bursts: 1200* for more than 30 seconds.Unloaded Max Bursts: 1300* less than 30 seconds longLoaded Sustained Bursts: 1200* all day long.

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I always had thought 1350 max sustained, and I've been very angry at my EGTs lately and have let them sit at 1400 for 10-20 seconds on occasion and spike to 1500 sometimes.

nothing has melted yet

drag race driving empty I can spike to 1600 but that's for less than a second and I wouldn't really worry about that sort of duration at any temp

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I tend to agree wit ISX... Like even myself I might find myself pulling a grade in 2 gears lower 5th to 3rd... But I can stay below 1,100*F at 2K R's climbing 7% at 15K GCW... When you hauling weight speed is no longer a issue. Get in line with all the other turckers and take you time.

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1250° max continuous1300° maxThose are my personal numbers, and would be the same on a 2nd gen. If I am nearing the top of a grade I let it go above 1250°, and if it looks like it will go above 1300° I bump the CC down a mph, usually good for a 25° drop. It's all about airflow, 1300° at 1500 rpms will put more heat into the piston than 1300° at 2200 rpms. Towing temps are more critical than short bursts empty due to the sustained temps. 1500° empty on a quick WOT run probably wont do anything, but hold 1500° while towing for 30-40 seconds and you may have issues!

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Guy on another forum has an 05 fairly modded and tows at really high egts all day on road trips, I think I read he will run 1400+ and has not had a problem.

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Guy on another forum has an 05 fairly modded and tows at really high egts all day on road trips, I think I read he will run 1400+ and has not had a problem.

A lot depends on the timing. Stock timing on an 04.5-07 will produce 1450° EGT's while towing, if I were to try that now (if I could get there) things would melt.

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I tend to agree wit ISX... Like even myself I might find myself pulling a grade in 2 gears lower 5th to 3rd... But I can stay below 1,100*F at 2K R's climbing 7% at 15K GCW... When you hauling weight speed is no longer a issue. Get in line with all the other turckers and take you time.

I haven't even posted in this thread :lmao: Nevertheless, I will pass someone and turn a blind eye to it, but the more I tinker with the truck the more I realize that 1200 IS a possible limit while still having the same amount of passing power. I have a very hard time going over 1200 even with the trailer and passing someone. I have pulled it 1000 miles and passed several people on 2 lane roads and the highest I have seen is 1235. Raising the RPM's and lower the MPH is key. If your over 1200, then your RPM:MPH ratio is off, raise the RPM and lower the speed..

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Yes when I do tow and when it hits, 1250ish, is when the truck is slowing down as the mometum falls off from starting the hill. Whwn I reach that egt the rpm's are usually around 1600 and falling. Which then I usually downshift to a lower gear. Like mike said pulling a good hill, I am in the right lane with the rest of them. Usually humming at about 2-2100R's and about 900-1000egt.I cant remember where I heard it but suspposedly during the testing of the 6bt Cummins tested it at: IIRC 2500rpm full load and sustained 1200egt, for some stupid amount of time: 24hrs?

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I pull 9000 lb trailer over a 6% grade mountain fairly regularly. 5th gear (nv5600) 55mph up, maintaining that speed ticks around 1150-1180, sometimes 1200-1230*F if I have a head wind.24valve, Edge Juice on 2, 24psi up the hill. Coolant temps usually climb to just over 200-205.Cruising 68mph, 6th, empty, flat ground(ish), 6psi, 880-910*F.Cruising 65mph, 6th, loaded, flat ground(ish), 8-12psi, 950-1125*F.

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I haven't even posted in this thread :lmao:.

Mike was thinking that you posted what I posted, so he is very confused. That is ok, because we both know that he can get help somewhere, even possibly over the rainbow, for his neurosis.:lmao2::lmao: :broken:Still I think that 1200* or less all day is the best temp to keep the engine components from melting.

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The other thing to consider that EGT's have an effect on is oil temp. I am not sure what year the piston cooling nozzles started in, but I have seen oil pressure go from 58 to 43 on a hard long pull with the stock turbo. That's some warm oil!

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My question is this.Aluminum meltdown @1220*Short bursts of heat are ok because the piston is not soaking the heat and causing the aluminum to be molten. With a stock turbine working the choke point and sustaining the 1200 towing EGT temp so them I'm guessing we are going to be more looking at possible melting on the crowns from a quick short burst over 1200 if we have been towing @ max gvwr.Example: I'm towing weighing 17k lbs. I am running a hill and keeping it 1100-1200.. I start to crest it go to shift hit 1300 for a moment. If the metal is at 20* from melting and then you put more than 80* over it then I am figuring your (I am and had) taking chances.People if you have a piece of aluminum go heat it with a torch. It's unbelieving how fast aluminum will be molten then back to a solid.I have a cummins piston and I'm going to do a test if I can get some measuring equipment..

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My question is this.Aluminum meltdown @1220*Short bursts of heat are ok because the piston is not soaking the heat and causing the aluminum to be molten. With a stock turbine working the choke point and sustaining the 1200 towing EGT temp so them I'm guessing we are going to be more looking at possible melting on the crowns from a quick short burst over 1200 if we have been towing @ max gvwr.Example: I'm towing weighing 17k lbs. I am running a hill and keeping it 1100-1200.. I start to crest it go to shift hit 1300 for a moment. If the metal is at 20* from melting and then you put more than 80* over it then I am figuring your (I am and had) taking chances.People if you have a piece of aluminum go heat it with a torch. It's unbelieving how fast aluminum will be molten then back to a solid.I have a cummins piston and I'm going to do a test if I can get some measuring equipment..

i have question to add to this question;

if your egt is 1200* how hot are your pistons? is the oil and the cooling jackets not taking some of this heat away from the pistons?:shrug:

--- Update to the previous post...

I pull 9000 lb trailer over a 6% grade mountain fairly regularly. 5th gear (nv5600) 55mph up, maintaining that speed ticks around 1150-1180, sometimes 1200-1230*F if I have a head wind.

24valve, Edge Juice on 2, 24psi up the hill. Coolant temps usually climb to just over 200-205.

Cruising 68mph, 6th, empty, flat ground(ish), 6psi, 880-910*F.

Cruising 65mph, 6th, loaded, flat ground(ish), 8-12psi, 950-1125*F.

just throwing this out as a comparison from my trip back to Elizabeth city NC;

grossing about 21k

70 mph empty, 6th gear, flat ground 4 psi, 750-800*F

70 mph loaded, 6th gear, flat ground 10 psi, 850-900*F

i am reading boost off of the MAP sensor. not sure how accurate it reads.

egt's are coming from a themrocouple in the exh manifold.

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I agree! What if though your oil temp is high because of ambient temp and load and your coolant is standing on 195* some factors for me during hay season and hauling.. :shrug:

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When towing heavy, my oil temp has gotten up to 222* on the temp gauge that I have installed. This is when I was going up a 7% grade, towing about 15K. The coolant temp only got up to 200*.

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Combustion temps are far greater than the EGT gasses we measure, 2500°+ on a heavy tow. But the temp quickly drops as the piston goes thru the power stroke, and the temps are only that high on 3/4 strokes. It's not the flash temps that melt pistons, it's sustained cylinder temps.

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When towing heavy, my oil temp has gotten up to 222* on the temp gauge that I have installed. This is when I was going up a 7% grade, towing about 15K. The coolant temp only got up to 200*.

Not to hijack but where is your oil temp gauge. I want to install one as well but havent decided if in the pan or off the filter housing. Maybe even the turbo return line? Not that the turbo would be indicative of engine oil temp but I am guessing the most brutal area the oil has to see would be in the turbo.

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Not to hijack but where is your oil temp gauge. I want to install one as well but havent decided if in the pan or off the filter housing. Maybe even the turbo return line? Not that the turbo would be indicative of engine oil temp but I am guessing the most brutal area the oil has to see would be in the turbo.

I would run the oil filter housing. I would like to find a place on the block to run it, but I am not sure there is one that will work. There is a port on the block just above the ECM, but I don't tink a 1/8" sender will get deep enough with the NPT to metric adapter to get accurate readings?

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Posted Image

Right on top of the oil filter housing there is a plug that I used. In the picture, you can see the turbo oil line and the oil temp sensor.

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