All,

The truck in my sig has an ISB235 with a turbo-back 4" with glass pack, gutted torque tube and missing silencer ring. I have also performed the tone ring mod, but only the dowel hole and nothing more. 110k miles on the clock.


I don't have gauges (other than factory) and I have been reading quite a bit about high EGTs dropping valve seats and ruining motors. I want to make sure this doesn't happen to me. With the derated 235, I spend a lot of time at or near WOT in the hills when towing. I have noticed the engine temperature climbs to about 210-215 when pulling hard.

I'd love to hear your thoughts on this. Can a (almost) bone stock SO ISB produce dangerous EGTs? Unlike many, I don't care about power. I just want this engine to outlast the truck it's sitting in.

Thanks in advance.

 

Get an EGT gauge. These 3rd gens can get quite hot on there own. Stock, mine could get up to 1400.

 

Thanks. I'll be adding one soon. I know the straight exhaust will help EGTs some. Are there other measures worth taking? Boost fooler or something? I really don't want to start messing with programmers and the like, but if there are some basics I can do to prolong longevity, I'd like to hear them.

 

Yep my 2007 5.9 pulling my 35' horse trailer will EASILY get to 1300 before shifting down ( I have a G56). I never let it get over 1300. As soon as it is getting close I shift down even when I have lots more go pedal

 

Clack,

While it's always good to have gauges, I really don't see how you could hurt yours with stock programming. Maybe if you had a clogged air filter or air intake it would, but the gauge might help you catch it.

Your timing might be more retarded than the HO in 04, and that could lead to a high EGT, not sure. I've also heard about dropped valves. What a nightmare that would be! With my Smarty and advanced timing my temps don't seem to want to get north of about 1200. I don't like them getting over 1100 and tend to back off a bit or, even better, get the RPM up. That really helps. I've learned that things work a lot better at about 2200 RPM than at 1600 RPM, under heavy load. not only the EGT, but the tranny lockup clutch.

 

A stock 03-04 engine should be around 1200-1250 degrees max for the EGT.

MikeyB

 

mickeyB is correct. the 04.5 up with the third injection pulse are the ones that run hot, it does not hurt them at all to run 1400* all day long. a smarty jr is the best. it will lower egt by about 250* change the cam to a ddp or a colt. change the turbo to a he351c from a 04.5 up. have the nozzles honed 35hp. on the exhaust . the reason for the cam change in early 04 models the cams were changed to the new incylinder egr scheme for the 04.5 up. take the tone ring off. the smarty does it dynamically where the tone ring is fixed . the jr is way better at timing. leave the jr set on default tow. we tow very heavy (up to 44,000 lbs cgw in the mountains) with this setup. the nozzle honing is not for more power but to shorten duration. by not going to performance on the jr. you do not have to worry about over fueling the available air. get a psm kit and the new mopar filter.

 

oops that should have been a pdr cam. ddp hones the nozzles

 

The most effective way to decrease EGT is to pump a higher rate of air thru the engine.
High load low RPM operation gets hot QUICK. You can see EGT get dangerous within 10 seconds pulling hard at low RPM. By simply shifting back one gear and spinning the engine up, you increase airflow thru the engine dramatically. This is your best friend at controlling EGT when working the engine hard.
True diesel engines like our Cummins are designed to run at rated speed all day long without insult or injury.
One other thing that can/will cool EGT is to increase the efficiency of your charge air. There is a formula for determining how much temp drop in exhaust you can acheive by dropping charge air.. but I can't remember what it is. I've gotten lazy and use a manufacturer specific program for all that info anymore.

 

I'm impressed, all the replies I agree to. Higher rpm makes all the difference... lower egt...not lugging the motor and 24 valves breathe........better. Just beware, cylinder pressure is a major concern when changing timing. Just because you can gauge egt don't get all comfortable. The in cylinder pressure of aftermarket timing versus stock timing does increase PSI. But the cummins is built to withstand it to a point. So does anyone know what the factory stock combustion psi is?

 

Thats a loaded question.. hahaha..
Combustion pressure is going to be dependent on a laundry list of variables. Piston speed, IMAP, IMAT, cylinder temp, fuel quality, etc.etc.etc....

 

The EGT is usefull for more than just maximum temperatures. I use my EGT mostly when shutting down the engine. I wait till it drops below 350*F. You'd be suprised how long it takes in the summer with the A/C and pulling the boat trailer. FYI

 

Here's a thread that talks about the difference between the previous turbo ('03-'04.5) and the redesigned turbo HE351 ('04.5+). It appears the upgrading to the newer stock turbo will help EGTs.

https://www.dieseltruckresource.com/...s-t216958.html