Exhaust Gas Temperatures

[HBarlow]

Maximum EGTs that our engines can tolerate are frequently discussed in these forums. I have been concerned about EGTs in my vintage Gen II truck because if I don't watch the pyrometer on a full-throttle climb it will peg the needle at 1600° under some conditions. The problem is reduced since I had the radiator fins pressure washed.



I read with sadness the recent thread here by our fellow TDR member who lost the engine in his '04 while pulling RVs for a living. He cited high EGTs and wondered if his symptoms were unique. Another owner of a similar truck reported similarly high EGTs.



A friend, who is close to a Cummins insider, told me recently that '04. 5 and '05 trucks typically produced EGTs in the 1375° to 1425° range depending on altitude during Cummins testing.



The Cummins insider reported that current Gen III engines were built to tolerate such temps and satisfactorily tested at those levels.



This information doesn't necessarily mean earlier engines can tolerate such high heat or that we can add injectors and boxes without risk but it does tell me that aluminum pistons don't necessarily melt or fail with EGTs above 1300°, at least not on Cummins 600 or 610 engines.



Harvey

 

[rbattelle]

aluminum pistons don't necessarily melt or fail with EGTs above 1300°, at least not on Cummins 600 or 610 engines.



Harvey

I agree... the key is sustained temps that high. Brief periods are okay. We must bear in mind that the pistons are very effecively oil-cooled. It's amazing what a little cooling can buy you.



-Ryan

 

[Papa Delta]

I was under the impression

that the 600 engine was designed to run all day at 1300. I have my box set to cut off at 1350. I would never stay that high for any extended period of time.

 

[KYLE4]

you don't want to be in the 1600's at all turbo's don't fair well either do heads or exhaust manifolds 1,2, or 3rd gen trucks

 

[MegaRocks]

Hey Kyle4,



What about my 600 with stock exhaust, Pup on performance, Westach thermo installed in manifold before turbo? How hot is o. k? Gauge shows about 1300 getting on the freeway! Truck is real fast on performance mode!



Because of where I installed the thermo, is that temp. o. k?

 

[jnelson]

Cummins does not have any spec temps on pre-turbo temps. Only post-turbo. Cummins reccomends not to exceed 1100* post turbo. Cummins says probe failure in the exhaust manifold would result in catastrophic turbo damage.



I can attest to having EGT's in excess of 1450* for periods of a minute or so. When pulling a loaded GN up a grade I can watch the EGT's go has high as 1550*. I have installed a Quadzilla intake, a Magnaflow 4" free flow muffler (going to stacks) and my ATS intake will go in this week. I am going to do what it takes to get 400,000+ miles out of this truck. I dont need pre-mature engine failure at 175,000 miles cause my #5 piston get a hole burned in it. I would rather spend $1,000 in helping the motor cool than $8,000 on a new motor.



. 02

 

[Vaughn MacKenzie]

I've been a member of this group dating to pre-TDR (July 1999) and have seen a number of guys melt down #6 of their 24-valve at sustained temps around 1250-1300 and even less. Some get away with more. Don't forget gauges can be off, and when you're running to the limit there's very little margin of safety.



Another way to hurt your motor is stacking boxes and still running the stock turbo with a blocked wastegate. . . not a good idea, especially if you want to get any decent service life out of your truck. Drive pressures go to the stratosphere, the exhaust turbine is very restrictive, and it's a good way to blow head gaskets or crack or warp a head. It's one of those things you can probably get away with but will take a cumulative toll, and by 100-150k you'll seeing signs of a tiring motor . . .



Vaughn