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i had a thought to get a database kinda of egt temps while running at a certain speed to see where we all stand compared to each others different setup. also to assist in baselining some info. Mainly its to get an idea of EGTs with each setup. If you have a gauge post up, if not dont guess. (this isnt a competition, its to help all of us out)

 

I will start...

 

@70mph my egts are appx 750F no headwind and outside temp about 75 deg

@65mph my egts are appx 620F slight crosswind temp 70

35" tires

6th gear nv5600

stock setting

RV275 injectors

HX35

level road surface NO load

Edited by CUMMINSDIESELPWR

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At 70mph, 6th NV5600, Smarty SW5 POD 85, OEM injectors turbo and level road:

 

600*F +or- about 25*F

70 mph

6th gear nv5600

edge comp 5X3

rv275

265 75r 16's

HX35

level ground

around 750*

215 '96, 280 Bar, 285/75/16,  NV4500 5th gear,  

~75° Ambient Temps

 

Averaged over the course of 47 minutes on I70.

EGT's - 680.4°F

Pre IC - 185.3°F

Post IC - 79.0°F

Boost - 7.9 psi

Drive - 9.4 psi

RPM - 2071

MPH - 73.0

 

 

Edited by Cowboy

Stock. OEM Injectors and turbo, 47RE, 285 75/R16. running 70 mph 2-3 miles

 

800 degree F

4-5 LBS boost

Edited by 01cummins4ever

...

Edited by CSM

  • Owner

@65mph my egts are appx 650F no wind and outside temp about 75 deg

18-20% Engine load

40-50 HP (flywheel)

120-130 FT/LBS (flywheel)

 

@55mph my egts are appx 550F no wind temp 75

235/85 R16 tires

5th gear nv4500

Edge Comp 5x3

+50HP injectors Vulcan Performance

HX35

level road surface NO load

 

 

65 mph

265/70/17

G56 in 6th

level road

7-10psi boost

60 ambient

550-600deg

285 M/T tires

Edge EZ

RV275's

2" leveling kit

 

At approximately 70 mph in 5th gear (5 speed) the EGT's will range from 650-750* and boost will generally be around 5 psi, depending on the levelness, ambient temperature, and wind.

Running 255/80R17, 245/70R19.5, or 285/70R17 with my NV5600 in 6th on a flat road I am ±50° of all of the below temps on a 75-85° day. 

 

60: 600°, 1-2 psi

65: 650°, 2-3 psi

70: 675°, 3-4 psi

75: 700°, 4-5 psi

80: 750°, 5-6 psi

85: 800°, 7-9 psi

 

It's been a while since my drive pressure gauge was hooked up but its going to be about 1-2 psi less than boost. 

 

My next run to town I'll do a quick data log for a mile at each speed and post the averages. EGT's will be post-trubo thou. 

 

70mph,4.10's, 80-90*, 255/85/16

8-10psi and 800-850 egt.

i am in the process of switching to 3.54's and will update when the swap is done

Empty I'm about 750-800 egt at 65-70 mph, my quad doesn't seem to affect it at all on any level if I don't get on it. My tranny temp is around 150-160 at that speed. 

  • 1 month later...

Made a trip a couple months ago, lost the SD card but just found it... lol

 

215 '96, 280 Bar 7x10's, 265/75/16,  NV4500 5th gear,  

~70° Ambient Temps

 

Averaged over the course of 6 minutes.

Pre-EGT's - 641°F

Post-EGT's - 525°F

Pre IC - 163°F

Intake - 92°F

Boost @ Turbo - 8.2 psi

Boost @ Head - 7.7 psi

Drive Pressure - 9.4 psi

RPM - 2080

MPH - 71.0

 

Also Climbing a short hill at 70 mph.  These numbers are not averaged, but taken once everything steadied off.

 

Conditions are the same as above

Pre-EGT's - 797°F

Post-EGT's - 601°F

Pre IC - 184°F

Intake - 97°F

Boost @ Turbo - 14.6 psi

Boost @ Head - 14.3 psi

Drive Pressure - 15.0 psi

RPM - 2086

MPH - 71.1

 

So what EGT is dangerous for these engines??  I remember the early days of the cummins 262  we wanted to stay under 1100 degrees but would push to 1200 to top a hill. Those were the temps where you needed to cool out to 650 before shutting down.

If the thermocouple is placed in the exhaust manifold and reading the back three cylinders (not post turbo).....and you trust your pyrometer, then the suggested "maintained" EGT is 1250*.  But quick bursts above that are considered acceptable.  How high and how quick?.....I wont comment since thats a do at your own risk thing.

As far as I can tell there is no published info.  1250*f sustained is what most agree is safe.

 

 

As far as my highway egts 

 

60: 650-700

65: 800

70: 900

 

I really can't get temps below 600 regardless on the highway but mpg are above 20 at 60 so I don't worry.

4 hours ago, oldbeek said:

So what EGT is dangerous for these engines??  I remember the early days of the cummins 262  we wanted to stay under 1100 degrees but would push to 1200 to top a hill. Those were the temps where you needed to cool out to 650 before shutting down.

 

 

Long time since I heard anyone mention a 262.  Drove several different ones.  I drove a 300 small block at one time and that one you needed to be pretty careful to not run over 1250* with it.  Had to drop gear more than one time.  I have an old book I acquired from somewhere years ago describing the proper use of a pyrometer and 1250 was max number according to it.

10 hours ago, oldbeek said:

So what EGT is dangerous for these engines??  I remember the early days of the cummins 262  we wanted to stay under 1100 degrees but would push to 1200 to top a hill. Those were the temps where you needed to cool out to 650 before shutting down.

This is quite a question.... When towing I'll stay below 1300 on both pyros no matter what. Can it take more heat? Probably, but it's easier to drop a gear and make sure I get the load where it needs to go.

 

On the other hand, I've pegged my Quadzilla pyro. It reads a max of 1834 (Not a typo) and I know it was higher than that. Engine still runs great. How long can it hold that heat before melting the pistons or the turbine on the turbos? That's the million dollar question!

On my truck I'll run 1250° continuous and will allow short bursts to 1300° when towing. When I am not towing I don't care as much but I have a very difficult time breaking 1150° without a trailer.

 

 

There are several factors that effect max sustainable EGT's and of those timing is the biggest. Prime example is the 04.5-07 5.9's. With stock tuning they are safe at 1450° sustained but on a tuned engine those temps will melt pistons.

 

The QSB480, highest rated 5.9 from Cummins, is a marine engine that has a manifold temp of 1301° at rated power/rpm. I would really like to get a copy of that ECM to see how it's tuned.

Edited by AH64ID

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i play it safe and have it all to defuel @1250. if im pulling that much heat ill downshift, id rather take a little more time climbing than kill another engine lol