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I'll state it one more time, lol.

My 1250 degree max sustained exhaust gas temperature limit I use when towing is not opinion, or something I used a devining rod to arrive at.....

It is the exact specification given for my engine by International Navistar (the engine manufacturer)

This value was arrived upon based on the ability of the under-piston cooling jets to shed piston dome heat, the ability of the valveguides to shed heat and so on.

More than 1250 and they deem the heat to be a run-away and the engine's expected service life might be compromised.

As to the reason a short burst up to speed will not hurt your engine, it has to do with "Heat soak" for lack of a better term. It just physically takes time to heat up an given component. That's why intermittant temperatures can be much, much higher than steady-state temperatures.

Take a torch with a flame temperature easily hot enough to blow straight through a piston. Now take a pair of pliers and stick the piston in the flame and right back out. Would you honestly expect the piston to have a huge hole in it, lol.

It takes time. And usually long before you've gotten the actual piston dome temperatures high enough to hurt something on an short burst you're going so fast you're out of road anyway.

This is why steady-state towing is the only time egts are not something to mess with.

To put it in perspective, I am actually VERY conservative with my egts compared to nearly anyone making good power with a light diesel.
 

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can you post the source of the 1250 sustained temp? you keep referencing it, and for the sake of arguement id like to know where you got it from and what series/model navistar engine this applies to.

can you post the source of 1300 sustaned cummins egt?
 

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I made it all up. Well kind of anyway. A case of beer and a Wigi board told me......

:eek:
 

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I made it all up. Well kind of anyway. A case of beer and a Wigi board told me......

:eek:
lol, if your are going to post fact, then im only asking for the basis of this fact. i dont find it an unreasonable request. im not calling you out, i just think if its a cummins and navistar fact, then you obviously have supporting documents.

im trying to keep my information current. my beer and wigi feels 1300 is high for sustained egt. but if im wrong, id like to be able to see for myself why.
 

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Haha. I didn't read it anywhere. Years back the 7.3 powerstroke (International Navistar T-444E) racing community wanted a concrete number for maximum sustained exhaust gas temperature.

We contacted the engineers themselves and they got back to us with 1250* pre-turbo for durated service. I do not know if they posted that figure in any literature since.

I also spend a good bit of time at the track and obviously the 5.9 is a hell of an engine, so it's everywhere. I remember being pissed years back when I learned that the sustained egt for the B series was higher than for the Powerstroke. I cannot conclusively remember if it was 1300 or 1350 so I went with 1300.

I can ask around to any number of the cummins performance shops near me and get a conclusive number. Jeff Garmon lives less than an hour from my house and I go there pretty often. There are numerous 700+rwhp fuel only 5.9's there. One is over 850rwhp fuel only and one of their trucks is over 1000rwhp.

I'm sure that he can tell me where pistons fail. Otherwise, I'm sure there is literature on both of these subjects with their respective engines somewhere.

I'll look for you. How bout that?
 

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We contacted the engineers themselves and they got back to us with 1250* pre-turbo for durated service. I do not know if they posted that figure in any literature since.
who is "we"? if you (you would actually be part of 'we") contacted "the engineers" then you should have received some type of document outlining the claim. you arent going to tell me "they said on the phone" i hope! and you say you dont know if has been psted "since" implies you have a copy.

so you dont have any data, charts, engeneer specs to back up what you have been posting as fact. i AM NOT ATTACKING YOU. i only think you should not argue your opinion as "facts". the average diesel turbo user feels 1200 is the safe range. you keep posting the opinion you have read and heard that 1300 is what cummins rates it for, and trying to post it as fact. the peoblem is this would be an expensive lesson for a guy to come here and follow your advice, imo.

if cummins believes that 1300 is continuous rated then there WILL BE A WRITTEN DOCUMENT stating such, provided by cummins. since they have to warranty the "fact" that 1300 is acceptable.

im patiently waiting.
 

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I have been reading the posts on here over the last few days, some good stuff by plenty of good well meaning people. Charles included.

Accept Charles, your personality is abrasive and it shows in your writing. I believe you have a lot of good knowledge to share but your downfall is you subscribe to the pecker race, and often I am afraid.

That being said I will have to back you up on this one. I too have heard the same, no paperwork to back it up though. I once jumped an all-knowing individual over on the DTR who happened to work for a diesel engine manufacturer, called him out in personal message luckily. We traded PM's and in the end I believe him. Of course I confirmed this later from a Chrysler engineer. It is not unheard of for the Cummins to run with sustained 1300 egt, but that will not be happening in anything I own.
 

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im calling him out.
i dont believe for one second a 6bt with a stock bottom end will swing 6000rpm reliably. i google searched his quotes and am unable to find ANYONE that says that it was a stock bottom end.

my 4bt has seen 10000rpm with 3500degrees pulling up the side of hoover dam and toting 600hp with a cam from a honda vtec engine.

i said it on the net, and im a briggs and stratton engineer.

doesnt make me right, or correct.
 

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Well I appologize then.

The biggest difference I see between that remark and myself is that I really do what I say and have seen nearly every possible way a powerstroke can break, because I've done it myself, or been a part of the analysis when it happened to another engine. I've held the broken parts in my hand knowing what the temps were and knowing what the live cylinder pressures were as graphed through the use of cylinder pressure testing equipment with respect to crankshaft degree. I know exactly what to expect with a given boost pressure and timing or any combination of the two, not through what I read somewhere or heard someone say, but through EXTENSIVE time consuming, and expensive testing on my own and others engines (engines that take around 8k on average to fix and over 20k in many instances). So taking known chances with engines with price tags like that is not what I do. Testing is one thing, but I need not do anymore exhaust gas temperature testing..... I KNOW where they fail, and how they will fail, and how long to expect them to live at a given temp and so on and so forth.....time and time again I KNOW this.

I KNOW where the stock rods will fracture. Not from word of mouth or something in a book, but from Live cylinder pressure testing and more broken bottom end components than you can imagine through the testing process.

Do you honestly think you could produce 482rwhp every day for years on an engine designed to make around 200rwhp if not for THOUROUGH testing and development? If my knowledge base was so horrably skewed, how could you expect my truck to tow what I tow even one time? Let alone the hundreds upon hundreds of trips that my truck has completed and still has better than average compression on all cylinders with an untouched OEM longblock.

If you actually knew anything about the powerstroke you would quickly realize that the temperatures that I run sustained are VERY conservative as is my general approach to engine building. My truck is a daily driver and as such has to be 100% dependable. Only a couple months ago I drove this truck from Atlanta Ga to Niagara Falls Ny to pic up the little 4BT that I'm working on now. About 11 hours into the trip up and at about 1:00 am somewhere in the middle of nowhere Pennsylvania, I ran across a chevy 350 powered S-10 that was not going to be happy until he blew me off the road. So probably over 700 miles from home in the middle of nowhere at 1 am I had enough confidence in my engine to go full boost all the way through 3rd, into 4th, all the way through 4th, into 5th and finally around 125 or so I pulled past him and put 5 lengths on him before lifting. (I however, in no way promote street racing)

While many people actually trailer vehicles to the track, producing power even to, or slightly higher than this truck, I drive and tow other vehicles to the track with it. That speaks volumes about the amount of faith I have in my setup.

That faith was earned through years, and years of testing and testing with the unavoidable failure here and there. It is not blind foolishness, I assure you.

Other than the realm of the dependable daily driver, I am CONSTANTLY around and a part of competition diesels. Wether drag racing or sled pulling. I have personally worked on vehicles ranging in power from mid 400's to over 1200hp. I spend a good bit of time at the dyno tuning and verifying what works and what does not, independent of however it might "feel".


I would appreciate it if some could refrain from the constant attempt at completely discrediting me with respect to light diesel performance.

And I appologize for my tone. I'll try and work on that.
 

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so, you will clutter a 4bt board all about your "navistar/international" experiance that only you have, then bad mouth a few of us, who have actually RUN a 4bt and have the equivelent 4bt experiance you have.

so if bob says high egts do not work too well, you slam him. then you post a 105hp 4bt sucks in a heavy truck, and i wear your ass out with my actual experiance and VIDEO proof, then you try and slam me. your right. ill call you out. run your buggy in the 1/4 with about 1700egt and 6000rpm and on the road for about 100,000 miles and ill apologize to you... man to man.

i cannot slam what you say with a navistar as b.s. and havent done so. you quoted "engineers" said "......." then i call you on it and you cant produce anything. why not just say you did it and it hasnt been a problem then to try and justify it with facts that cannot be produced?

if i would have said "i pulled out two stuck vehicles tied together" EVERYONE on the net would have said B.S., you were on solid ground... blah...blah...blah.... my video is what PROOF i need.

im not going to try and discredit you on every post. ill discredit you and anyone every time i see an opinion posted as unarguable "fact"
 

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The 1250* info was actually directly from International Navistar's engine division. It was over a Chat program years ago powered by "Icechat" and through the channel "Ford-diesel-chat" of of "The Diesel Stop" server. I guess you would also not believe that Gale Banks also made a personal appearance in that same chat room would you?

And that although for the B series cummins engines I have not the same level of personal experience, but have garnered through long-time relationships with those who have forgotten more about those engines than you will ever know, that the maximum sustained egt is 1300.

So I guess you have "equivalent" experience with your 4BT as do I with the powerstroke? You have personally built and run over 20 sets of different injectors? You have run dual injection pumps? You have done extensive live cylinder pressure testing under full load and full boost? You have tried multiple types of head sealing "gaskets" and found what you like? You have completely re-designed both fuel and oil circuits from the ground up?

Many I am more than sure have much, much more than equivalent experience with the B series compared to mine with the powerstroke........you however, I know for a fact, are not one.

All of your "knowledge" over your engine is what you have heard from others as your engine is actually bone stock. Congradulations on the wealth of experience that must have bestowed upon you. If that counts as "experience" with a 4BT, then I more than likely have more than you, lol. My Case forklift is 4BT powered and I assure you I have more hours running it than you have driving your truck in one year. Nearly every Lull/Skytrack used to have the B3.9 before they went to the 4.5 I believe. I drive one nearly every day.

I have "run" many, many more 4BT's than you in reality.

Being that my truck is a diesel, and it came stock with ~200rwhp which was sufficient for most driving empty, but was not enough for actual work duty out of a 1 Ton truck when actually towing something other than a bassboat, do I actually have to feel what less than 100rwhp does in order to know it's a complete turd in an equivelant vehicle?



confused
 

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I just re-read this entire thread from start to finish just to try and see where it all fell apart, and to see where I apparently started the "problems".

I would honestly urge anyone feeling as though I have been unsympathetic and childish to re-read my posts from the begining (there are not that many) and actually take the time to read them and see where my target was.

Then notice that my tone only changed to one of frustration and sarcasm after having what I stated "called" out more than once.

If you wonder why one could get frustrated, imagine having actually had a chat room conversation with the men that actually built the engine in question only to have someone write this about your actual account of the event after your having contributed that information in the hopes that it might further someone else's understanding of just exactly what egt's mean, how to interpret them and when coatings should be considered.



(Mcinfantry Quotes me)
Quote:
Originally Posted by Charles View Post
We contacted the engineers themselves and they got back to us with 1250* pre-turbo for durated service. I do not know if they posted that figure in any literature since.
Quote:

(Mcinfantry then writes)
who is "we"? if you (you would actually be part of 'we") contacted "the engineers" then you should have received some type of document outlining the claim. you arent going to tell me "they said on the phone" i hope! and you say you dont know if has been psted "since" implies you have a copy.

so you dont have any data, charts, engeneer specs to back up what you have been posting as fact. i AM NOT ATTACKING YOU. i only think you should not argue your opinion as "facts". the average diesel turbo user feels 1200 is the safe range. you keep posting the opinion you have read and heard that 1300 is what cummins rates it for, and trying to post it as fact. the peoblem is this would be an expensive lesson for a guy to come here and follow your advice, imo.

if cummins believes that 1300 is continuous rated then there WILL BE A WRITTEN DOCUMENT stating such, provided by cummins. since they have to warranty the "fact" that 1300 is acceptable.

im patiently waiting.



Does that not spit in my face? The "I AM NOT ATTACKING YOU" is akin to simply ending the sentence, you are a lousy good for nothing piece of shit, with "No offense".

Just read my posts in the thread from the begining and I do not see how I can be seen in a bad light.

Thanks,

Charlie
 

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Group Hug


There isn't that better?


Now back to beer drinking and talking about women....ere um.. I mean engines.:smile:


RW
 

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Bob you were right, should have taken your advice... Thread closed, nice work gentlemen.
 
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