Survey, egt's

[buzzinghalfdozen24]

What's everyone's egts? Towing, uphills, level ground, loaded unloaded etc. I have just installed a wicked wheel and an afe waste gate. Curious if I'm being too hard on myself or not. I can reach 1400 deg uphill accelation, not loaded. 70mph on interstate is roughly 750-850. It just seems I can't keep exhaust as cool as I'd like, and I don't even have crazy tuning or anything. It responds just about the same when detuned. Ideas?

Probe is mounted at the Y where all 6manifold meet and join with the turbo.

Also love to hear if guys with tuners are using the "overdrive-off" setting, and are manually kicking down to 3rd lockup when towing up steep hills and not able to maintain high enough speed in 4th. Built trains handles loads perfect, but I'm thinking I'll be safer to back down on speed and use third vs fourth. Running 70mph up steep hills it just bakes the pyro, I'm pretty sure I've grazed 1600 a time or two but was letting off the throttle pretty hard haha. She still pulls awesome has has pedal left and doesn't loose power at all, but just buries the pyro...

 

[cerberusiam]

Tires are likely your biggest problem with a standard gear ratio, too tall and wide. The 60 HP injectors add enough fuel, any extra tuning just makes it worse.

I am running a lot more injector than the 60's and there is no way on even 34" tires to keep it in check on long grades. It is borderline as is with 33's, tops around 1300 when I am running heavy on long or steep grades.

The taller tires also mess with the OD functionality. You just have to cycle the TH button and watch the temps. I have the BD OD lockout and use it frequently.

 

[buzzinghalfdozen24]

Good info, thanks. Gear ratio has came across my mind a lot too. I think 3.73 would make up for the tires. But 4.10 would probably be better. I figure it would help keep the rpms up and turbo spooled. But, I doubt I'll ever change ring and pinion sets, ha-ha.

I'm just glad to know I'm not the only one that notices and doesn't like these things. I suppose without changing gears, or tires, twin turbos would probably be only air flow solution., that would actually solve this. I've been eyeing a banks ram air elbow, the 3.5" with boost tube. I think that would help eliminate a factory restriction.

A lot of people say the factory exhaust wheel of the turbo is the limiting factor, so don't know if I'll ever fix that issue. Don't want to buy a turbo and have done research and wasn't too happy with the negative side effects of larger turbos. So I figured I'd try to modify oem, since lag time is about half of aftermarket turbo units. A friend praises water/meth injection. But I want nothing to do with injectables.

 

[NIsaacs]

Tires are likely your biggest problem with a standard gear ratio, too tall and wide.

Changing gears or tires won't help, It will just change when the over heat occurs. Anytime you can force the truck to use full power the heat will be there. It just might take a bigger hill or load.

Nick

 

[promisedland]

With my stock [as far as i know] inj and a 90 hp tune i see about 550* at 70 empty unloaded.

 

[DaveHess]

I always like reading what other people are seeing for EGT and the combination thay are using to get those numbers. Running empty down the interstate at 70 mph will get me about 600 EGT. My probe is located just in front of where the two ends come together and head to the turbo. Basically behind #3 cylinder. Anyhow, I run about 17,080 pounds gross combined pulling the TT and loaded with camping gear. I will run about 67 to 70 MPH towing (TT tires being the inhibitor), on flat and level and no wind, I will see around 900 EGT. I run my Smarty Jr. on tow all the time. On longer grades and when speed starts to slide towards 60 MPH, I'll kick out the O/D. What I will see before the kick-out will be somewhere around 1250 to 1300 EGT. Once I kick out the O/D and get boost back up, It will commonly drop back to 1000 EGT.

One thing of note here. Several years ago, I bought an adjustable boost elbow. Over the course of several tows, I tinkered with the setting. I now have the elbow setting where it is blocked off. The most boost I see is 29 to 30 PSI. More commonly 25 to 27. The more I shut down the boost elbow, the more decrease I saw in the EGT when pulling hard and taking the 48RE to 3rd. So, right now I am very happy with the results. CERB, please chime in here if you see something wrong in what I did here.

 

[cerberusiam]

With the 3.73's you just can't go beyond 33" tires and approach the GCVW without issues, even stock. 34's are nominal and even with stock injectors and just mild tuning. Can still push that temp constantly to 1200-1300 degrees in adverse conditions. With a 32-33" tire and same conditions 1100 is pretty normal for max an cruising at 1000 is about right. Gears will completely change the way that works, all you have to do is watch load percentage differences and it becomes obvious.

I have tried running 34" tires grossing around 20k and the truck just does not like it. Not enough gear to make the leverage optimal, 35' s would totally unusable for most of the loading I do. You basically have 2 options, more air and gears. At some point even the more air is going to come up short in a set of towing twins and then gears are the last option.

You can open the air box a bit, add a intake elbow, open the exhaust, add a larger IC and the gains will be minimal changing nothing else. You might get a 100 degree drop at certain rpms but it won't change the max that much. The 3rd gen system is pretty effective up to the point you go beyond its design, then, you have to change turbo, gears, etc, to significantly impact the outcome.

Bottom line, if the temps are exceeding 1300 for too long on stock tuning it is time to do something else.

 

[promisedland]

I used my Touch to turn off my waste gate, at WOT i saw 40psi boost which is ok [SW5=90hp on my Smarty] but what spooked me was, my drive psi i was up at 70psi!! This is what i saw before i had Tater mod my stock turbo. But then my wastegate was turned on....

On normal driving i see 10psi boost to 11+ psi drive psi. Drive psi gauge is steadier with the moded turbo. I haven't done a WOT run [waste gate on] yet since swapping my turbo. I have been tweeking my gauge/tubing set up.... i have plugs i put in my tubing because i dont normally need it connected. Also have a air chuck fitting to blow out my copper so it dosnt fill up with soot. Fun!

Once my trans and T-case are built, [in 3+- weeks] i'll check it again with the waste gate on.

 

[buzzinghalfdozen24]

Great information. I mistyped, I do think my truck has 3.73 gears. I agree with everything said.

I'm gathering that more people are manually kicking down to third lock when towing. Glad to hear. I will eventually do the boost tube and elbow from banks and possibly an intercooler.

I just don't know about doing a turbo. I feel I'm not going to be pushing enoughbfuel honestly to justify a new turbo. That's why I stay with stock. Everyone says just put a turbo one, exhaust wheel is restrictive. That's all true, just don't know if I can capitalize on an aftermarket turbo. Downsizing tires next time, that I can do.

How about wastegate adjustments? Anyone know how much difference it makes actually adjusting the thread length? I set it as AFE suggested... Maybe a turn, to psi ratio??

 

[promisedland]

So you have more to ponder.... Tater moded my turbo for $1100 done. Whistles like a Cheetah!
I have an adjustable wastegate turnbuckle from BD here... i got it for my hx35 2nd gen but never put it on,... maybe i'll see if it fits.

 

[NIsaacs]

Don't want to buy a turbo and have done research and wasn't too happy with the negative side effects of larger turbos. So I figured I'd try to modify oem, since lag time is about half of aftermarket turbo units.

I agree and I am in the same boat. I will also say that our trucks (mine is '01) are not apples and apples. However, excess heat is excess heat no mater what you drive, so I will be watching this thread to see how you improve your rig.

Since my truck is manual I loose all boost every time I shift. Especially loaded, I shift slow and easy and pause a second and make sure my clutch is hooked before I get back in it. In my case this helps in the fact that this slow shift will drop my temps by 200* every shift. So the small factory turbo is what I need. It works great up to about 2100 rpm, then goes stupid after that. And that is ok because I don't like high rpm anyway, but on a steep on ramp when I need about 2500 rpm to get another gear it is an issue. I have to drive by the gauges.

Empty I have no problem at all, I can hit my default speed (85) my Edge will shut off before the temps get hot. I just changed my factory exhaust (3") to 4" so I am sure that will help some but I am also sure it is not a total cure, I will know as soon as I can tow. My next plan is to start working on my waste gate settings to help the high rpm drive pressure. My turbo will never work at 3k rpm but that is ok, all I need is about 2500 and only once in a while.

All this is testing on level 5, with the Edge Juice, my normal setting.

Nick

 

[p-Bar]

Maybe EFI Live with a good custom program ? Just talking out loud .

 

[buzzinghalfdozen24]

Maybe EFI Live with a good custom program ? Just talking out loud .

I've researched and researched for years. Apparently there's some ecm differences on 05 trucks. They don't have efficient live for my truck. Just 06 and up.

I always thought the Cummins lineup was 03-04, and 05-08. But for some reason 05 is an odd year. I understand the elms were different in 03-04, but thought when they jumped hp in 05 the tuning and ecm stayed the same through 08. Apparently I'm out of luck, cause efi live with custom tuning would be amazing

 

[cerberusiam]

HP Tuners and Smarty UDC for the 03-05 trucks. The 03-05 trucks had MANY revisions of functions and ECU's, partly because the protocol was a proprietary one. The 06 trucks went to CAN bus and have all been that since. The amount of security around the ECU is what is changing a lot from 09 on. The 2013 trucks have now integrated all the trans, body, and engine controls back to one ECU.

 

[buzzinghalfdozen24]

Good info. If only I'd have bought one year newer of a truck. Too much work done now to sell it. I've got a bully dog but don't think it's a good match. However I've recently started liking the "overdrive-OFF" setting in the BD unit. With that setting I can limit my egts at cruising speed by having the engine downshift to third and have converter lock.