Engine/Transmission (1998.5 - 2002) E.G.T's and ambient temp

[Sageair]

all other things being equal if I tow the same trailer up the same hill at the same speed etc will my egt's be 50 deg higher when the ambient temp is 100deg than when it's 50 degrees?

 

[jerrethomas]

i would say yes. the effenciey of the air to air cooler declines the hight the ambient air temp. it can't cool the air going into the engine as well as it could when it was cooler.

 

[Whitmore]

I have ram air system on my truck and a temp senser at the air horn, pretty much when empty I run temps at ambient or slightly above but when you get the 5er on the horn temp will go to 115-120 pretty easy and then if you turn on the a/c at the same time the temps will climb to 145* under a heavy load on a 100* day.



Cheers, Kevin

 

[TomGolden]

I live in the Sacramento, CA area. Winter temps average in the 50's, summer temps in the 95 - 105* range. I see a 100 - 150* increase in my EGTs in the summer, and that's running empty and not towing anything.



I drove to my parents house for the July 4th weekend. They live near Barstow. It's 440 miles, down Californias central valley, then over the Tehachepi mountains. Every last mile of that trip, ambient temps between 100 - 107*, going between 75 - 80 MPH at fairly constant speeds, my EGTs were 850 - 900*F, engine oil temp was running a pretty constant 200*F.



On this same trip in the winter, or even just running around Sacramento, my EGTs are in the 600 - 700*F range, might run as high as 750*F or so running over 75 MPH.



Comp is on 2x3 all the time, except when racing.



Tom

 

[Hohn]

Ambient temp makes a big difference for two reasons:



1-- intercooler efficiency

2-- how hot the intake charge gets depends on how hot it was to begine with (among other things)



I see a 150° difference between extremes. . \\jlh

 

[Sageair]

Thanks to all who replied. Steve.

 

[dremelts]

You also have to take into account the calibration of the EGT gage itself.



The gage is actually displaying the *difference* in temperature between the probe in the manifold and the cold junction at the other end of the wire in the gage housing in the cab. The gage manufacturers usually set them up for 75*.



So, when the engine is "cold" and both ends of the thermocouple are equalized the gage should read 75* even if it is really 0*. As you regulate the inside temp inside the cab and maintain it at approx. 75* the gage reading will be more accurate.