Yep I did a Google search after I posted the question. Looks like sdp posted it on a couple forums.

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2005 Crd Silver Limited- arps, rockers, 7v etechno's, egr deleted, v6 airbox, metal cac's. Yeti's stage 2 tune. Euro TC, Ram tcm, pml transmission pan, facet lift pump

That should be good for a really great 1/4 mile time.... Once. I look at performance and reliability as two sides of a pendulum. You can pull the pointer more to one side or the other, but eventually you are going to run out of the one you are moving away from.
Trying to double the power (for example) of an engine is definitely not going to be good for its lifespan.

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Proud supporting vendor of LOST Jeeps
TRAVELING CRD TECH. I come to you!
Need help? Just ask! I've taken it apart more than most.
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Over 125 CRDs currently driving with my timing belt, rockers, or ARP Studs.
Bad noises = REALLY bad things.

Thats what you said about my engine lol. Its not really the hp that shortens the lifespan, its the guy that has control of the hp that determins it, the right tuning helps tremendously as well.

Im going to message the guy to gauge if theres any interest in a bb turbo upgrade, if so thay could really help these take ahold, and ultimately lower the price (bulk order of everything).

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05 Liberty Limited CRD, converted to KPA 2863 ball bearing and billet turbo, 50hp injectorsl, complete egr delete, cooling fan delete, weeks intake kit, cummins in tank lift pump, ARP studs, 3" turbo back exhaust, samcos, etecno plugs, GDE trans tune, custom GDE engine tune.

I still wish you much luck and success... And I'm happy to watch from the sidelines. These engines are strong, but they have some weaknesses that need to be dealt with. The valves for one. Have you looked at having something better manufactured for yours, or are you not worried about the cylinder temps?

On that note - do you have any specific numbers that you have recorded from your experiments / research about the EGTs? Pre or post turbo? I'm having a hard time getting solid numbers from people, not many have an EGT gauge.

I always measure pre turbo, i want to know what the temps are coming out of the head. I have the alarm led on my gauge set for 1,200°F. Ill get up to 1100 acclerating from a redlight, 1,400° if i lay into it to pass 4 cars in a row. SDP (the guys who have the twin turbo kit for the new 2. were reporting 1,800°F on a 85hp tune. GDE told me when i got my custom tune that we were safe up to 1,400.

Remember part of my temps are the direct result of having a larger than normal turbo. There isnt enough energy to properly drive my turbo until higher in the rpm range. People with the factory turbo should have lower egts than me.

I honestly havent been worried about valves, but if a better option became available id def jump on it! Im focusing more on the turbo stuff, better intercooler included. I have my eye on used BMW X5 twin turbo diesel suv to replace the liberty. Once i get one i want to pull the liberty in and go through the engine. Check the bearings, install performance cams, blah blah. If you can get better valves ill be one of the first to jump on the wagon.

Only weakness i really see is our louzy cylinder head, both in flow and bolt pattern. The place that scanned my turbo could scan a cylinder head easily enough. From there things could be changed, but it doesnt change the dumb bolt pattern.

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05 Liberty Limited CRD, converted to KPA 2863 ball bearing and billet turbo, 50hp injectorsl, complete egr delete, cooling fan delete, weeks intake kit, cummins in tank lift pump, ARP studs, 3" turbo back exhaust, samcos, etecno plugs, GDE trans tune, custom GDE engine tune.

Thanks for the numbers!

I agree with you, stock should have lower EGTs, unless they are dealing with an EGR leak. Although that also begs the question, if there is reduced boost, then there is less air overall, how come the EGT would be higher? That requires both fuel and air, and a richer mix will just hit the smoke point faster. Thoughts?

I seem to remember rolling down the highway with my EGT probe (in the mouth of the turbo) reading maybe 900-1100 at my usual 75-80mph. This was with the stock turbo and an eco tune. I'm curious what you think the difference would be in temperature if the probe was closer to the cylinder though? It is only about 3 inches away from the exhaust valve of the #2 or #3 cylinders, and I can't believe the temp would drop any significant amount in that short area.

The stock valves seem to be failing in the alloy section though, so with these kind of temperature numbers... That is very very odd. Even mild steel should be able to handle temps like that!

I believe the GTB turbos have a bit more temperature resistance than our turbos do. Not sure if it's just the turbine itself or the vnt mechanism as well.

The Colorado is using a gtb1752vk. I honestly am surprised they can run that compound setup with that much power and flow it all through that gtb17 turbine. The VW guys seem to think the 17's start to choke just over 200whp. I guess the exhaust pressures must be huge but that's not a good thing.

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2006 CRD - GTB2056 turbo by Dieselguy86, Eco Trans Tune, Lift Pump, Week's, HDS Tstat, Racor Filter, ARP's, OME 790's+Top Plate, JBA 2.5", JBA UCA, Moab's+265/75R16, ARB Bull Bar, 4.10's, TrueTracs

This article gives a good explanation of diesel EGT:
http://bankspower.com/techarticles/show/25-why-egt-is-important

Basically, more fuel (rich) = higher EGT
More air (lean) = lower EGT

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U.S. Army Retired

Which jives perfectly with what I've always heard too. But then there is the typical description of the use of EGR: To "cool" the exhaust. That obviously is not the result, so once again it seems that EGR and boost leaks might be the root cause of failures on these things.

_________________
Proud supporting vendor of LOST Jeeps
TRAVELING CRD TECH. I come to you!
Need help? Just ask! I've taken it apart more than most.
Email jeep [at] maincomputer [dot] com - BOARD MESSAGING IS BROKEN
Over 125 CRDs currently driving with my timing belt, rockers, or ARP Studs.
Bad noises = REALLY bad things.

It "cools" by warming the charge air, making it less dense. Less dense air means less oxygen molecules, so less fuel is injected to meet the requested af ratio. Less fuel, less heat.

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05 Liberty Limited CRD, converted to KPA 2863 ball bearing and billet turbo, 50hp injectorsl, complete egr delete, cooling fan delete, weeks intake kit, cummins in tank lift pump, ARP studs, 3" turbo back exhaust, samcos, etecno plugs, GDE trans tune, custom GDE engine tune.

Those 35d's are fantastic. I test drove a 335d before I bought my f150 and the thing was pretty stout on the stock tune. I've heard some pretty awesome numbers just from tune only.

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2006 CRD - GTB2056 turbo by Dieselguy86, Eco Trans Tune, Lift Pump, Week's, HDS Tstat, Racor Filter, ARP's, OME 790's+Top Plate, JBA 2.5", JBA UCA, Moab's+265/75R16, ARB Bull Bar, 4.10's, TrueTracs

Not really wanting to tweak that one, need the extra room for our 3rd kid coming and i want an inline 6, not the v6 that everyone else has.

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05 Liberty Limited CRD, converted to KPA 2863 ball bearing and billet turbo, 50hp injectorsl, complete egr delete, cooling fan delete, weeks intake kit, cummins in tank lift pump, ARP studs, 3" turbo back exhaust, samcos, etecno plugs, GDE trans tune, custom GDE engine tune.

That is less a function of temperature changing as it is simply replacing the fresh air with unburnable carbon dioxide. Whether the computer can or does accurately adjust the fueling, is subject to some debate. The computer could easily detect that there is a boost leak if the MAP is reporting the difference between requested and actual boost pressure, but it doesn't unless the actual boost level is basically zero. The TDI has the same problem... For about 4 seconds. If you open the boost hoses completely, it will detect it and toss you into limp mode where it basically disables the turbo entirely and cuts fuel to match. Surprisingly on the TDI, you can still drive it at 70mph with a hole in your intercooler and in limp mode! (I did it after a debris strike) The CRD is not that smart. From what Keith has said, the MAF is only used to detect EGR function, not to meter the A/F ratio at all, so that theory of EGR flow is out the window.

What I see happening is if we have EGR flowing, people will just put their foot deeper into it to get the power they want until the computer kicks out of EGR flow and shuts the dang thing. That adds fuel / heat to the fire and cooks things. Ditto for boost leaks. Since the computer doesn't even want to kick into limp mode unless you blow a boost hose entirely off, it has a VERY high tolerance for boost leaks. Not good.

The maf is used for egr operation as you said, the map (or more specifically tmap) sensor will detect the hotter air and adjust fuel accordingly. How much and how well it works is up for debate, but thats the theory of how its "supposed to work"

People have been arguing that egr is useless on diesels for years, but the epa says we have to have them. Atleast we dont have to deal with dpf and def.

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05 Liberty Limited CRD, converted to KPA 2863 ball bearing and billet turbo, 50hp injectorsl, complete egr delete, cooling fan delete, weeks intake kit, cummins in tank lift pump, ARP studs, 3" turbo back exhaust, samcos, etecno plugs, GDE trans tune, custom GDE engine tune.

Right, it does not seem that our jeep's tunes account for actual MAF to determine proper afr. It just assumes that if the boost is X then it can inject Y fuel. There is an "AFR" map in the tune that tells the ECU what the max fuel can be for a given boost level so if your turbo isnt making what it should it will eventually hit a ceiling determined in this map. It is a high ceiling, and you would be blowing a good amount of soot out the tailpipe. If the IAT's increase and air density lowers then it will burn richer. A bigger CAC for us will not necessarily increase power since fueling wouldnt change for a given boost, it just may burn cleaner/leaner.

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2006 CRD - GTB2056 turbo by Dieselguy86, Eco Trans Tune, Lift Pump, Week's, HDS Tstat, Racor Filter, ARP's, OME 790's+Top Plate, JBA 2.5", JBA UCA, Moab's+265/75R16, ARB Bull Bar, 4.10's, TrueTracs

A properly functioning EGR valve should have little effect on EGT.
The EGR valve should only be open while the engine is at a steady cruising speed. At this point, EGT should already be naturally low.
All the MAF does is sense when the airflow rate is best for the EGR to open.
Now, if the EGR were stuck open, that could create problems at high engine loads.

The MAF isn't used for air fuel ratio because it doesn't matter.
Without a throttle body to control how much air goes into the engine, all that can be controlled is the amount of fuel. So at low engine loads, air fuel ratio will be high (lean) and at high engine loads it will be low (rich).

More fuel = more power = higher EGT

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U.S. Army Retired

I dont think egr really messes much with egts, like i said its used to lower the density of the charge air to prevent nOx. However this increases soot output, which is why pre def engines used dpf filters. Later they found out they could squirt urea in the exhaust to also reduce nOx, which meant they could back off on the use of egr, freeing up power and some pre-emissions efficiency.

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05 Liberty Limited CRD, converted to KPA 2863 ball bearing and billet turbo, 50hp injectorsl, complete egr delete, cooling fan delete, weeks intake kit, cummins in tank lift pump, ARP studs, 3" turbo back exhaust, samcos, etecno plugs, GDE trans tune, custom GDE engine tune.

They just waste raw fuel into the exhaust to re-burn the already unburnable soot and make the particles small enough to be unseen (but the perfect size to penetrate DEEP into your lungs just like the soot from a Prius already does) so I don't think they care about the soot other than making it smaller. Gee, you can't see it so it must be gone / better, right?

I'd like to see some actual facts that they have reduced the amount of EGR because now there is urea injection. Somehow I get the feeling their actual decision was "Oh good, urea also reduces NOX (which really is NOT a pollutant since it breaks down in hours into nitrogen and oxygen)... So lets inject that to further reduce levels after the massive egr use has also reduced nox!

"But but but Mr anti-diesel science guy... Burning raw fuel in the exhaust and using this much EGR reduces the efficiency, so they are burning much more fuel and creating many more pollutions that then must be reduced! Wouldn't reducing fuel use (with better efficiency) be a smarter angle? Less fuel burned always means less emissions."

"Quiet! I'm on a crusade to make diesels as inefficient as gas engines, so people will complain about them and buy more priuses!"

Ah... It starts to become clear.

There is nothing good about an EGR valve on a diesel engine!
Dumping hot exhaust gases into the intake manifold can raise combustion temperatures and in turn raise EGT's leaving the cylinder. This is bad for the exhaust valves which we already know some are having a problem with them breaking...

From a site that gives a pretty good explanation as to why an EGR system is very bad for a diesel engine and is not needed!

Remove the EGR Valve – It is Very, Very Bad for Your Diesel Engine!
The first of which is, slightly worse fuel economy. Exhaust gases don’t re-burn all that well because it contains very little that is “useful” to the combustion process. So when you reintroduce exhaust back into the diesel engine, you are displacing fresh air that has more oxygen with exhaust gasses that don’t. As a result, the engine doesn’t burn the fuel as well because there is less oxygen.

Diesel exhaust by its very nature has pollutants in it, including soot in the form of carbon. By re-introducing the untreated exhaust back into the combustion chamber, soot will start to buildup in the oil and on other internal engine parts, including the intake turbo. This is NOT good, it’s debatable just how bad it is. I’m of the opinion that the cleaner the air going into the engine, the better it will perform and the less problems you’ll have in the long run. This is the whole reason why vehicles have air filters. The EGR system does not pass the exhaust back through the air filter because there is way too much soot which would clog the air filter in a matter of minutes. So if the EGR process is too dirty to pass the exhaust through a filter, think of all that black soot that is going directly into your engine.

Because exhaust is hot, it must first be cooled prior to re-mixing it with incoming air. Piping 700°F gasses into the engine is a recipe for disaster. Therefore, an EGR cooler is required. It is basically a small second radiator that reduces the exhaust gas temperatures before they released into the intake manifold and re-burned. If the cooler fails or looses its ability to transfer heat, the intake temperatures of the engine can skyrocket quickly causing permanent or fatal damage. The EGR Cooler also adds a lot of heat loading to the cooling system that must be removed by the radiator. Dumping hot gas into the intake also kind of defeats the whole purpose of the Charge Air Cooler does it not!

Is the EGR valve needed? The answer is a very big NO!

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05 Jeep Liberty CRD Limited
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Yeti StgIV Hot Tune
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2mic.Sec.Fuel Filter
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V6Airbox/noVH
GM11 Bld.fan/HDClutch
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98 Dodge Cummins 24 Valve

Yes, the diesel doesn't care so much about afr, but by not using the maf you really don't get a good idea of how much air is actually making it to the cylinders. You could have two 2.8l engines that both run at 20 psi of boost, but one could flow 20lbs/min of air while the other flows 25. The one flowing 25 lbs could burn 25% more fuel, but without a maf the ECU has no way to know that since boost only tells part of the story. They just have to sort half booty what the boost should be for a certain amount fuel by trial and error and testing. If we ran a new turbo on the Jeep, we may very well have to do the same.

At least for full throttle where you would be pushing afr's down into the teens, a maf could be a good thing to have.

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2006 CRD - GTB2056 turbo by Dieselguy86, Eco Trans Tune, Lift Pump, Week's, HDS Tstat, Racor Filter, ARP's, OME 790's+Top Plate, JBA 2.5", JBA UCA, Moab's+265/75R16, ARB Bull Bar, 4.10's, TrueTracs