HOHN

Exactly. I'd say the Cummins could probably handle 1300 all day! That said, you'd better have a good gauge and hope it's accurate.

FYI-- a STOCK HO 24V truck will hit and sustain 1300 pulling heavy load, so I don't think that momentary flashes to 1400 or even 1500 will hurt anything.

My truck has only seen super egts once-- on a Superflow dyno that put more load on it that it has ever seen. 1550°

On the street, it never sees 1400.

JLH

600 Megawatts

Yep, 1,300°F non stop 24/7 indefinitely. Coolant temp and oil temp is important as well, and not nearly talked enough about on here. EGT's are beat to death on here...



KP

Geico266

Just remember, aluminum melts at 1220F. At what temperature does it get weak when it is exposed to cylinder pressures?

Actually, I run my airplane around 1,300F all day long. I monitoring all 4 CHT's (cylinder head temps) & EGT's The pistons run cooler than the egt's due to the cooling effect of the fuel/air mixture, and lube oil.

DR3500

that truck had another problem, it should not have been anywhere neat that for the conditions. 1250 deg. is the max I would run sustained. more momentarily.

LanceD

would a water/methanol injection system help with EGTs?

also what does a set of those fancy aftermarket pistons cost?

Rockyhud

pgilles (and for everyone else too),
My temps are pre-turbo - propably should have mentioned that earlier. Also, to Bill's point on gauge accuracy, I have no reason to suspect the gauge/thermocouple is not accurate as my EGTs correspond very closely to what I've read others get, particularly at idle and typical no-load hi-way speeds.

Kevin brings up another good point and that is the engine cooant temp. I monitored this at the same time as the EGTs to see if it was getting higher during my run across Kansas and sure enough the coolant temp was elevated - a little above the 190 mark but not too much higher. EGTs had been running quite a while at the 1200 mark, and so considering the outside temp at the time was bouncing betweem 102-104 F* and I was running the A/C on the coldest setting, plus having had the winds pretty well torn my top cover tarps to shreds, I decided to slow down some to allow the engine to cool down to it's more usual temps and to prevent loosing any loose items in the top of the trailer.

Here's another thing that just came to mind while reading the responses so far. It would seem that with the thermocouple being installed in the manifold where it picks up the gases from the last 3 cylinders, wouldn't this tend to indicate the highest temp gases coming from the engine, presuming the front 3 cylinders run somewhat cooler, based on the premise that #6 is the hottest? Based on that presumption, and from what I gather from most of the responses so far, I take it that running 1200-1300 continuously won't cause harm and that these EGTs are going to be the hottest coming from the engine. If that's indeed the case then it sounds like you guys have once again helped me determine what's best for my truck and the way I drive it. I can't thank you enough. Plus, it was a great debate on the topic. I enjoy getting other people's thoughts and knowledge on things like this.

So, on the coat-tails of this topic, what changes would you recommend for my turbo, considering that we will be living in Colorado again (yea! ) and that while most of the time the truck will be driven with no load, there will be times when I'll be towing our Jeep CJ on the car hauler trailer to trails around the state (and elsewhere like Utah) going over whatever mountain passes are in the path?

Steve

cumminsdriver635

I personally dont like to run anything over 1150* sustained. My truck will peg my 1500* gauge evewn empty, but i always let out of it as soon as i peg it. I dont think it makes much difference as long as you dont hold it there all day. If you are just there, and back, then your pistons probably arent anywhere near 1500 degrees yet anyway. I just dont like to push my luck, so i keep it under 1150* EGT's while pulling.

Eric

Bushy

1200*F is the most often used 100% duty cycle for our engines...if you intend to do this, then you should also know that while the powerplant will take it, the extended operation will result in heat saturation of the block/head/manifold etc....so, keep an eye on your water temps...they will eventually start to rise and you want to use that gauge as your secondary info source on heavy usage....

pb...

Bart Timothy

I agree with Bushy. 1200-1250* at 190* engine temps. As engines temps go up max egts must be kept down even further. The radiator becomes the final limiting factor in how much substained power you can use.

RowJ

Good point!
Typo error on my part...it was towing 25,000 lbs.
I have corrected the previous post.

RJ