Engine/Transmission (1998.5 - 2002) Not Happy With Towing EGT's

[SMoules]

this weekend i towed my 5er for the first time. It weighs about 10k pounds. On a flat grade I was doing about 60-65 mph in OD and the egts would stay at 1200-1250 degrees. Is this high or is it normal for what i have in my sig? Also my boost was at 8-11 psi.

 

[DWeiler]

With mine---see sig for the goodies i tow 11000lbs fiver with my 6 speed and Smarty on #3 and see 950 PRE with my B1-2 but i have a upgraged "cooltwist intercooler" which is good for about 100-125 drop in egt's. Might have to drop down on the injector size or turn the box off and run on sticks only. Run with the overdrive off--milage sucks but it may help. If i get above 1200pre i drop a gear and it helps alot,i'm in no hurry with that much weight and like to run at those speeds too. PS-- my boost is at 5-7PSI

 

[rweis]

900 Pre @ 65 mph (2k rpm).



I have LOTS of air and then added a little fuel. DD2's even run hotter than mach 1. 6's (EDM), but work for me. Smarty #3



Boost towing ~ 10 - 12 psi. Turbine not really running hard, but it is spooled (KSB1-B).



You have to get more air going through there (rpm's up) to get the EGT's down.



Bob Weis

 

[SMoules]

do u guys think it will make a difference if i go to a 62/12. meaning that the turbo will be working a bit harder.

 

[PC12Driver]

I've found that keeping the exhaust housing a bit tighter (smaller) works better for towing. Like you suggest, it keeps the turbo blowing harder in the midrange.



I have *zero* first hand experience with the SPS series, and what the trade-offs would be between the larger 71mm wheel vs. the smaller 12 cm housing. But I can say that my temps with my 62/12 don't run that hot with the fiver in tow and I carry a bit more boost.

 

[Cummins724]

What do you have the drag comp set at for towing? I bet some minor tweeking will do the trick. A Smarty would help for sure!

 

[Graphic man]

you could run a lock-out switch for the converter..... un lock it when you hit the hills and get a little more RPM's and cooler EGT's



you will need to keep an eye on the trans temp gage

 

[PC12Driver]

A Smarty would help for sure!

How so? He already has the timing advance from the Comp, and in steady cruise extra fuel isn't gonna help lower egts.

 

[NoSeeUm]

... .

but i have a upgraged "cooltwist intercooler" which is good for about 100-125 drop in egt's.

... .

Man thats huge. At less than 10 psi boost?



Jim

 

[NoSeeUm]

this weekend i towed my 5er for the first time. It weighs about 10k pounds. On a flat grade I was doing about 60-65 mph in OD and the egts would stay at 1200-1250 degrees. Is this high or is it normal for what i have in my sig? Also my boost was at 8-11 psi.

What was your RPM?



Jim

 

[SMoules]

in OD my rpms were somewhere around 1700-1800. I tried my comp in different settings(1x3,2x3,3x3) and there wasnt any obvious change. the only thing that i didnt try was shutting off the comp. now climbing up hills out of OD, the truck pulled great with egts around 1000 and the boost would reach 24-28 psi.

 

[JR2]

Sounds like me last weekend towing my 3500 lb baby trailer. . even with the comp off and the smarty set to fuel/boost I was at 1100 on even the smallest hill in when in OD. When I took it out of OD it was okay on small hills, but still got hot on big long hills. I think my 285/75 tires and 3. 54 gears hurt me too. OD at 65 at 1500 rpm is not good. I guess Mach 4's and an HX40 are not a towing combination.

 

[NoSeeUm]

in OD my rpms were somewhere around 1700-1800. I tried my comp in different settings(1x3,2x3,3x3) and there wasnt any obvious change. the only thing that i didnt try was shutting off the comp. now climbing up hills out of OD, the truck pulled great with egts around 1000 and the boost would reach 24-28 psi.

Yeah I had the same problems. I have a 5 speed and had to shift to 4th to control EGT after I put the M1's in. I think that I assumed just a little to much for what the truck could do. With the 285's it gets worse, I am 1600 rpm at 60 mph. I have not towed with the twins yet, but very soon I will.



Jim

 

[Gary - K7GLD]

Sounds like me last weekend towing my 3500 lb baby trailer. . even with the comp off and the smarty set to fuel/boost I was at 1100 on even the smallest hill in when in OD. When I took it out of OD it was okay on small hills, but still got hot on big long hills. I think my 285/75 tires and 3. 54 gears hurt me too. OD at 65 at 1500 rpm is not good. I guess Mach 4's and an HX40 are not a towing combination.

YUP - what works great empty on the streets, often works poorly towing in the hills!



We tow a 15K lb GCW with the stuff in my sig - absolutely NO EGT issues in some pretty steep mile-high Oregon mountain grades...



Vast power is sorta useless, if you can't use it when you need it! :-laf

 

[y-knot]

My God, I can't even imagine 1200-1250 EGT towing on the flats, Wow you should be concerned.



Once you get the engine right you should shift your attention to getting a good transmission cooler for that thing.

 

[MTatsch]

i run about 800 -900 pulling my 20' +5' gooseneck and tractor its about 12000#s and i have the comp box and supermental 120hp injectors but i have with the added timing of the box it runs about 75 cooler on level ground

 

[Cummins724]

How so? He already has the timing advance from the Comp, and in steady cruise extra fuel isn't gonna help lower egts.

As he said... . he isn't working the turbo. I am running the SS62 which is equivelant to a SPS62/80 & look at my sig. I tow 15k# daily through the mountains of PA & W. V. My egts never go over 1200* & I pull up 5-8% grades that run miles long. I tow with my comp shut off most of the time & only run Smarty SW3. If I shut my Smarty off & tow with my comp only... . I can see egts of 1400*+ easy on a long hard pull. The trick to towing with a large turbo is to beat the heat by getting the turbo to spool before the heat takes over. Smarty fuels hard right off idle which spools the turbo faster. The Edge fuels harder after 1800rpm... . too late! Remember that 2000rpm is the sweet spot for these cummins engines. If you keep the rpms at 2000 & watch your egt gauge... . it will drop down at a steady throttle. I'm only trying to help. I've tried every turbo that HT has to offer & the Supers are the way to go for a tow rig. Ask Brady himself & he'll tell you the same & recommend a Smarty. That is what he told me & he was right. Just my $. 02

 

[SMoules]

thanx for the info guys... Mtatsh, what turbo are you running? those r some pretty low temps ur running. I would love to be running those temps towing... .



So do guys think if i step down to a phat shaft 62/12 my egts will come down? Im startin to wander if i should look into one of Quads new boxes he has coming out. i read somewhere that somebodys egts dropped from swapping one in.

 

[SMoules]

great info cummins724, thats a huge drop in temps from the comp to the smarty. Also the edge starting at 1800 rpms being to late for the turbo makes so much sense. thats exactly what i seen but couldnt pin point it down. Still new to the towing world. this is a whole different ball game now than just creating lots of power and speed driving around with nothing behind u. Its going to be a challenge to get this down to where i dont have to delete power from my truck... ... ... im looking forward to itOo.

 

[Gary - K7GLD]

Smarty fuels hard right off idle which spools the turbo faster. The Edge fuels harder after 1800rpm... . too late!

Some folks typically confuse operating conditions when empty on the street vs loaded in the hills - yeah, rapid low RPM in fast acceleration from a stoplite is a plus for drag racers - but not really an issue for those towing up grades, where acceleration is slower and smoother, and usually from a much higher beginning RPM - few of us are starting up steep grades from a dead stop with our RV's! :-laf:-laf



In my case, the Smarty combined with my upgraded injectors provides added fueling that makes it pretty much useless in the hills, plus lacks the on-the-fly adjustability of the Comp - which leaves me choosing the Comp hands down over the Smarty for heavier loads in the hills.



Besides, contrary to popular opinion, the Comp DOES fuel substantially lower in the RPM range than a stock truck, especially as you get into the higher available settings!



Sure, more boost than my stock HX-35 provides would likely overcome the over fueling with the Smarty - but would also require more expense in head work, studs and O-rings than I feel necessary for my particular towing expectations.



As I've been saying - what is needed and works best empty out in the drag races in short bursts is NOT always what works best when towing longer distances in the hills!