gipsl67

I am getting ready to install a Pyrometer gauge and was wondering what temperature ranges I should see? We will also be towing a Travel Trailer that when loaded weighs in around 8000 lbs. I am wanting to know when I should get concerned when I see a certain temperature.

HorseHauler

keep it under 1300* pre-turbo and wait for 300* before shut down and you will be fine

blown32

Please fill out your signature so folks know what your truck is and what mods you have done.

For your question, everything is dependent on the truck, it’s modifications, driving style, altitude, speed, terrain, and location of the EGT probe

For mine with a pre turbo sensor (see signature for details on the truck):

600 - 850 on the interstate empty at 75 mph, 950 on major hills (long and steep grade)

900 - 1250 towing 8,000 to 10,000 lbs (box trailer with horrible aerodynamics) at 75 mph
- I back out just a little when temp gets to 1200 on steep grades. If I am not paying attention, it will climb past 1200 very easily on a long steep grade. (I live in the rocky mountain area)


Now from what I have read, my temps are a bit higher than those with similar trucks, could be the gauge or differences in the truck.

What’s safe? Good question, opinions vary but I read a post from a reliable source that a 3rd gen can run at 1250 all day and night and that short and infrequent periods pats are not a problem. Some even say that short periods to 1400 or so are ok but it scares me a bit.

Hopefully someone with more knowledge on what is and is not safe will chime in.

StevenB05

I have ran mine up to 1500 pre-turbo racing let up as soon as I hit it. I also run it up to 1350 on steep grades pulling 10k and haven't had a problem YET.

HighTen

It seems to me that someone with a totally stock truck shouldn't be able to reach dangerous temperatures; they should just build the Cummins that way expecially since it doesn't come with an EGT gauge. From this reasoning, a truck whose only modification is exhaust (like mine ) should be extra safe.

However, when pulling our ~8000 lb travel trailer, I still watch the temps and back off if it starts to go over 1250. Maybe I'm just a big scardey cat.

EDIT: BTW, does anyone think max EGT should be different from max sustained? Or can you just run at the max temp a lot and not worry?

RamRunner

HighTen,

I agree with your thinking that max EGT should be different from max sustained. I would not agree with anyone thinking that you could just run at the max temp a lot and not worry.

My thoughts come from my career as an airline pilot, where I get to watch the performance of all sorts of engine gauges all day long to get an idea of what's going on. One of our more important limiting instruments is ITT, or inter-turbine temperature, to measure the amount of heat energy between different stages of the power extraction process.

For a normal takeoff, the engine manufacturer (Pratt & Whitney) has a limitation of 785*C or about 1445*F.

If needed for a maximum power takeoff, P&W says a max of 816*C (1500*F) is ok, but is limited to a maximum of 5 minutes.

Once out of harms way, we would reduce to maximum continuous power, which is 800*C or about 1472*F. We could run around all day at this setting and not have to worry about causing any overtemperature damage to the engine.

The most significant high temperature damage is done to our turbines during the engine starting process. When the fuel is introduced into the engine, without enough airflow for cooling and acceleration, things can get too hot in a hurry. P&W has time limits for temps over 850*C (1544*F) during the engine start.

So I'd wager to bet that approaching an absolute maximum EGT when hauling 10K up a steep grade wouldn't hurt the Cummins, as long as you're mindful of how much time you run at that level. I'm sure that there's also an EGT range that is higher than "normal", slightly less than "MAX", but that you can run at all day long without any overtemperature damage to the durable Cummins.

Gotlift01

I've heard that the 3rd gens can go about 150* to 200* higher than say the 2nd gens. And yes sustained is way different than MAX, if you sustained 1350* all day long driving around, sooner or later you are going to start damaging stuff...............that is just way to much heat for way to long. Your pistons would probably look like a colorful box of crayons!!!!

On a stock 3rd gen, I wouldn't think that you would see over 1100* max, I haven't really played with one that hasn't already had mods done to it so I can't be for certain what to expect. I know on my 2nd gen with some mods, just cruising I see between 750* to 900* and can smack 1400* in no time!!

4x4not

I hit over 1000°F on mine all the time, but normal cruising it between 450 and 800. Max I can hit stock is right around 1300° but that takes a bit hill and lugging it a little. Downshift into 5th and temps drop a couple hundred degrees. When I had my Eliminator box (for a total of three days ) I hit 1550° ONCE and backed off real quick! I could easily hit 1400° with that thing in a heartbeat. I still have a stock "swiss cheesed" intake and a stock exhaust, but a straight pipe is in my near future, as well as an intake like a Scotty.

RVT223

I am in agreement with the fellow pilot above. There is probably a safe envelope where the engine/turbocharger develops maximum power for a short period as opposed to producing maximum continuous power. Somewhere in a prior thread I read that max continuous power is 1350F for up to 30 minutes in 3rd gen engines. Anyone have an idea on what a max power EGT safe limit is? I have seen over 1600F for about 10 seconds at the race track. I can imagine the turbo glowing red hot....just like a hot or hung start in a turbine.
Regards

tweeter

Here's another question: post or pre turbo? What's better and why? Anyone want to venture their opinion?

N.Johnson

Install pyro Pre turbo for the nearest combustion temperature relative to the aluminium piston heads! I have a stock truck 305/555 2003 and pulling a 7500# travel trailer have hit 1375 F. The grades I was on when it happened where in Northern California to the Oregon border in August with a 92 F air temp. I have briefly touched 1400 F before the wastegate opened at 26 psi ( stock truck) racing a Acura up the Salmo/Creston Hwy #3 in B.C. ( I out climbed the ricer,unloaded).The 6% plus grade goes on for ever. For me I have never let my foot out of it and this truck is engineered safe, temp wise mid you with no fuel boxes. On a side note whenever I get the pyro hot for a while the engine runs quiet after for a week or so and then gets to ticking? I really believe that running it hot is good for tiny injector nozzles. Blow that carbon out/off the tips.Hell on fuel mileage but lots of fun

West Coast

sorry guys wrong section