egt temps

[rdanley]

what is a safe temp range to keep you egt in on pre and post turbo?

 

[redneckdr]

EG's

1250-1300* pre-turbo. post will be 150-300* less. mine runs a steady 600* pre at 60 MPH, and about 450-500* post. i've seen some members say that the engine will take a constant 1300* pre, but i'd be a bit uncomfortable at that temp, sustained.

 

[LSMITH]

Personally I would be a bit uncomfortble at 850* post turbo, it is just too easy for there to be a large difference in actual temps. Pre turbo I would have no problem what so ever holding a steady 1350 all day long, I would not worry about 1450 untill I held it there for a minute or more. I think the EGT being dangerous is way over rated at 1250-1300, a 24V should have no problems running 1450 all day long if the oil cooler and engine cooling systems are in good shape. Just my opinions.



The other side of this coin is your setup and driving habits, if you have a solid setup with some balance in air and fuel and run the engine in the right RPM range you will not have EGT trouble to begin with. Do your hard pulling between 1900 and 2600 RPM with a 24V, you will have to really try to get the temps out of hand if your setup is even close to balanced. MHO, hope it helps.

 

[Blksheep]

I guess I should move mine to pre turbo,because mine runs about 600 deg. at 70mph with no load behind me. What would cause high egt's on a stock truck unloaded??

 

[CRegal]

blksheep

Switch over, or better yet, add another egt gauge pre. Then see where u r at. Completely stock on my eth I could get it up to 1250 unloaded at wot. Now with the mods I have, I cant get it to break 1100 unloaded.

 

[barryg41]

Never had a problem with high EGT's stock! But pulling long grades or steep one's with a load has. The stock setup always defeuled when I got in those kind of situations. LSMITH hit it on the head when he said having your RPM's in the right range. Keeping boost and RPM's up is a good way of keeping the EGT's down. Plus I found the auto trans runs cooler.



The PE EZ has taken care of that little probelm with EGT's.



I monitor pre and post temps with SPA products.

 

[redneckdr]

pre and post

i'm running a single Isspro EV EGT gauge. i put probes in both pre and post turbo. i know it's supposed to not work as well, but i ran the leads to a DP/DT switch, then to the amplifier for the gauge. i ran it hooked straight from the pre for a coupla weeks before i wired in the switch. i couldn't see any change in the preturbo numbers before i wired in the switch, and after. i only use the post turbo reading to shut down the truck.

 

[CTabor]

Ever class 8 truck I have ever throwed the hood over on, is post turbo if it works for them it works for me.

 

[barryg41]

CTabor, I guess most TDR folks like to see the quick response they get with pre turbo EGT's. I know the post EGT's are a little slower in response.



Does the class eight truck manufactors provide a post temperature range (safe operatiing range) in the manual? If so, that would be just as good.

 

[CTabor]

Cat says 950 that is post.

 

[KWIKKURT]

IMHO I recommend Pre Turbo. One reason is I have seen over 400 deg difference (pre-post) with different combinations.



Running over 1250-1300 pre Turbo for more than 20-30 seconds I think is not wise. When I installed three EGT gauges all Pre turbo for testing and to setup one (Proofing) Gauge to use for bench testing. I registered 200 deg difference in the three. So how sure are you that your gauge isn't off 100 deg??



Pistons melt at 1350?..... So sustained temps over 1300 are dangerious.



On the other hand I, Hvac and many others have Buried our Pyro Gauges over 1800 deg for runs down the drag strip and / or passing on the hwy with a trailer in tow with no aparent visible damage when we removed heads later for gasket replacement. This is for less than a minute (20+ sec)starting from a dead stop not pulling long hills with a load.



Water Temp is not a good way to judge if your egt's are too high. You could melt your engine down without ever raising the watertemp.



As for post turbo: it is better for knowing when the turbo has cooled enough for shut down. The other reason is the remote possibility of the Thermocouple breaking and going thru the Turbine wheel. Quality of the thermocouples has risen to a very high level. The one I sell have a life time warranty and I have never seen one break in the last 20+ years.

 

[RJOL]

Originally posted by Blksheep

I guess I should move mine to pre turbo,because mine runs about 600 deg. at 70mph with no load behind me. What would cause high egt's on a stock truck unloaded??

I don't think anyone answered this, but 600 deg (post turbo), unloaded, at 70MPH seems pretty high. Have you added injectors, or a fueling box, without modifying your wastegate? If not, I'm not sure why you'd be seeing those temps. Maybe the gauge is wrong???

 

[hammong]

There is a substantial difference in boost and EGT on my truck between 60 and 70 MPH.



My truck on -level- ground at 60 MPH with NO wind on a 70 degree day runs about 5. 5-6 psi boost at right around 550-600 degrees pre-turbo.



The same truck at 70 MPH in the same conditions on the same stretch of road runs about 9-10 psi boost, and 750-800 degrees pre-turbo.



I've seen "60 MPH" and "70 MPH" tossed around in this discussion thread, and you may not be comparing apples to apples when reading through.



Level-ground, no-wind, I say 600 degrees POST-turbo is probably about right if you're doing 70, and it's about 150 degrees too high if you're doing 60. If it's high, check your air filter to make sure it's clean - and check your boost to make sure you don't have any boost leaks. (should be about 6 psi boost at 60 level-ground).



Greg

 

[RJOL]

Well Greg, you may be correct that we are comparing apples to oranges, but all I can tell you is that my 5SP 4:10 2001 CTD runs unloaded at 70MPH on level roads, with the pre turbo EGT at 6-700 max. The boost is around 7-8psi. If he is seeing 600 post turbo, that mean he is probably really seeing 8-900 pre turbo. That, in itself is not a problem for the engine, but it seem a little high to me...

 

[Blksheep]

My truck is 100% stock,and when I drive home from work every night I watch the EGT and boost guage and it's 600 degrees at 5-7psi boost with no load. (at 70 mph)The highest I've seen is about 950 this was pulling a 37ft park model camper and the boost was 19psi.

 

[turbo lcc]

my truck also runs about 600 - 700 post turbo??? same with or without the j-hook on the wastegate???

 

[Steve Campbell]

A while back Piers replied to a thread with a formula for computing (Loosely) post to pre #'s. When pulling, there is 300deg (stock turbo) difference pluss 10 deg for each 1 lb of boost over 20. (I hope I got that right ) My truck runs 25 deg hotter than stock in worst case conditions. I am mainly using my post probe for shutdowns and to detect any changes from standard readings.

 

[IdaH.O.Train]

Just installed my EGT (post turbo) and Boost gauges this weekend. On a 300 mi return trip I was running a constant approx 550* @ 70 mph, boost was at around 4 - 5 psi.

 

[GTop]

My 2001 runs around 450-500 post turbo at 60 MPH. At 70 MPH it's about 600 post turbo. So there's a few of us running about the same temps.

 

[redneckdr]

EGT

yep, 450-500* post and 600* pre at a steady 60 MPH on the levelest ground i can find.