That's what I'm thinking. I spoke with Doug today, and he said he only spend about $150 total, and I think he had to have some pipes made. I'll have to post the details when he tells me about it, I was in a rush and couldn't talk long. His is all aluminum though. oh, and he did say he just moved the AC radiator closer to the radiator, and I assume he relocated the AC fan. Not sure if he has it all finished, but he said it was bigger than stock, so maybe it's not too bad for people with AC to fit a different CAC in there. I bet a stock fan would cool the AC stuff just fine since it pulls air all of the time.

-Tomasnc I have one that someone else previously did an epoxy repair on. Looks pretty professional, but it still leaks. Not enough to notice performance wise, or to throw a CEL, but still messy.

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05 CRD: H.D.S2 stat,WW Ironrock trilink&LCA's, OX rear,ARB front, 4.10's, ARB bumper, Suncoast,OME 3.5, JBA UCA,rock rails, Moabs&265/75 Duratracs, GDE tunes ,FFD fan,ARP's, 2 micron fuel, new valves,sasquatch battery tray & grid heater, tensioner relocated
Mech fan, VH & AC delete

Mountainman,

With my repair steamed clean you would say it was new. The epoxy levels out great but once pressurized the tiny leak opens up. According to the repair shop there is an accepted amount of leakage , i.e. small leaks are permissible. My leak falls into this category. I have not drips on the garage floor so that is cool

_________________
2005 Jeep Liberty CRD Limited
Build Date May '05
OME lift kit
Samco hoses
Weeks Stage 1
PMF EGR plug kit
ARP Stud
Cracked CAC repaired with epoxy filler

Yeah, if it's the upper passenger side one, the one I was thinking of just looks like soot build up, and my other leaky ones are the same, no drips, just this creeping soot that eventually becomes tar like and migrates further and further from the leak. I can't believe they went this cheap on the CACs. It's like they were made by Mattel. I'm excited about Dougs cheap option with no plastic ends. I'll text him now and see if he can get me the make, but I think he has to look it up, and he works too much, might take a while.

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05 CRD: H.D.S2 stat,WW Ironrock trilink&LCA's, OX rear,ARB front, 4.10's, ARB bumper, Suncoast,OME 3.5, JBA UCA,rock rails, Moabs&265/75 Duratracs, GDE tunes ,FFD fan,ARP's, 2 micron fuel, new valves,sasquatch battery tray & grid heater, tensioner relocated
Mech fan, VH & AC delete

I've looked for an OEM intercooler that could be easily modified to fit our CRDs. The closest I've found is the Euro Audi S3/TTS intercooler. The cost is $385 shipped. The dimensions I have for it are:

Inlet & outlet tubes are 2 1/4" O.D.

27 3/4" distance between the tubes at shortest point (CRD radiator is 25 1/2" across at widest point).

33 1/2" width across top at widest point.

28 5/8" width across the bottom at widest point.

16 1/2" height - not including the 1 1/8" mounting studs.

24" x 16" x 1 7/8" core dimensions.

I think the outlet tube could be cut off, rotated 90 degrees and re-welded in order to make it angle downward (like the CRD intercooler).


http://www.ebay.com/itm/OEM-AUDI-S3-EUR ... 86?vxp=mtr

_________________
2006 CRD Sport
GDE FT ECO tune, GDE TCM ECO tune, ARP studs, HDS-001 203F T-Stat, 3.7L nylon fan & Hayden 2905 clutch, Carter P76148M in-tank pump, Racor 245R122 filter head & 2 micron R25S fuel filter, Provent 200, Samcos, Fumoto F-102, Litens 920834A de-coupler, PML rear diff cover, OEM trans pan with welded in bung, JBA UCAs, full skids.

Thanks for looking at that and posting those details 95Z28A4.
There is definitely room for improvement in the CAC system.
It could be really useful and well worth looking at even with my premium for shipping.
The one thing that is a real bug-bear to me is the lack of temperature drop across the stock CAC heat exchanger.
It is really an under designed piece of excreta - appalling to see (in our hot summers) 2 degrees C clawed back across the unit when it should be in the order of 12-15 deg C in hot weather.
I've watched it for a long time now and basically installed the thermistors and CAC gauge to see if it was loading with oil and losing its ability to lose heat. No deterioration but it wasn't great to start with.

At best I measure 12 deg C in cool autumn and winter running (24 deg C ambient)
As I can weld Al with either MIG, oxy or TIG I am really interested in this but haven't had time to have a good go at it yet.

Running MUST improve if this is attended to.
Will study the heat exchange capacity of the unit you mentioned and go from there.
Cheers.

I can only monitor intake air temp from the MAP sensor.

My stock CAC can keep intake air temps between 30 and 50 deg F above ambient, depending on whether or not I have the A/C on.
So, driving around town on a hot 95 deg summer afternoon with the A/C on, intake air temp can be as high as 145 F.
On a cool 65 deg morning with A/C off, intake air temp will be about 95 F.

I have no idea if this is good or not because I have nothing else to compare to.
But I would hope that a aftermarket intercooler would do better.

_________________
U.S. Army Retired

I would get the biggest cooler you can since our jeeps run relatively high boost pressures compared to most cars on the road. I know my Legacy only ran 16 psi with a custom tune and my F150 only hits ~19 psi and then drops to 15 or so with a custom tune and both needed aftermarket CAC's to run well. The jeep pretty much hits 21psi and then doenst drop much below 18 by 4000 rpm, so its likely heating that air up nice and hot.

What are the total external dimensions of the stock CAC?

_________________
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

Our intercooler efficiency is actually quite good. It's right in line with or better than OEM coolers typically are. Garrett says 60-70% is normal, and I measured ours as better than that.

viewtopic.php?t=44175

According to this test it's right in line with a factory BMW cooler.

http://www.enginebasics.com/Advanced%20 ... st%20.html

Factory N54 intercooler:


Upgraded N54 intercooler:


However long term durability is a problem with our plastic end tanks. I would love an all aluminum intercooler with higher efficiency and durability.

_________________
05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.

Here's what Dougbob used. He did put it in an 2002 Gasser I think (converted to CRD), so I'm not sure if the radiator and other confines are the same. http://www.ebay.com/itm/23-5-x11-x2-5-t ... 1e760fb6ec

There's a link down a ways in their listing that brings you to a bunch more of their listings. For a little more $$ they have kits that come with pipping and such. Maybe worth while?

Thoughts?

Edit: Here's the thread that shows that CAC in the 02. viewtopic.php?f=5&t=79154

_________________
05 CRD: H.D.S2 stat,WW Ironrock trilink&LCA's, OX rear,ARB front, 4.10's, ARB bumper, Suncoast,OME 3.5, JBA UCA,rock rails, Moabs&265/75 Duratracs, GDE tunes ,FFD fan,ARP's, 2 micron fuel, new valves,sasquatch battery tray & grid heater, tensioner relocated
Mech fan, VH & AC delete

Ok, so its efficient temp wise, but what kind of pressure drop was there? It takes more pressure to spread air over a tall thin area vs a shorter, thicker one. If it takes 3-4psi on the stock cooler thats 3-4psi the turbo has to overcome, and overheat, to get the boost the ecm is requesting.

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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.

Good point, the CAC in the link of my last post claims .2 psi drop I think. It would be nice to at least make our turbos work a lot less if possible

_________________
05 CRD: H.D.S2 stat,WW Ironrock trilink&LCA's, OX rear,ARB front, 4.10's, ARB bumper, Suncoast,OME 3.5, JBA UCA,rock rails, Moabs&265/75 Duratracs, GDE tunes ,FFD fan,ARP's, 2 micron fuel, new valves,sasquatch battery tray & grid heater, tensioner relocated
Mech fan, VH & AC delete

Correct me if I'm reading this erroneously.

I'd like to know how it is feasible to interpolate the electronically governed speed beyond 4000 rpm and why would you indeed do that? There is no practical purpose. Why interpolate?

My impression of aftercooler efficiency figures after long-term observation and running are different.

Basically the calculated engine load I'm working with (from my AE and confirmed by UltraGage) is between 65 and 72% per the ECU output.
Same relatively steep hills and similarly loaded vehicle.
Prevailing conditions change of course - that is why I include RH measurements and whatever else I can provide.

At 42 C ambient (real temp) (using the same efficiency determination formula) the thermal efficiency is 1% at this load and high external temps with high RH. Incidentally I'm not using the MAP to sense intake temp. It is actually measured independently and @ gave 85% RH per method discussed below. I get an efficiency of 1%

Cool running:
Same hill very close to same load in vehicle:
AT 24 deg C ambient (actual) RH = 35%:


A/C running both times.
RH using a sling hygrometer and psychrometric charts (AKA adiabatic cooling).

This does not look as rosy to me as the other figures presented above.

As the main function of an aftercooler is to increase air density beyond what the T/C has produced and reduce thermal detonation (secondarily of course).
The goal is not excessive boost P but to increase air density for engine performance and 20 psi is relatively high for a road car. 6-8 is closer for most petrol driven jobs.

Incidentally EGT in mine isn't radically different in either case as long as engine load is within this range.

As the industry standard for efficient aftercooler efficiency is between 60 to 75% (when new). we are a long way away from that in my view.

I'd re-state that mine has not changed notably relative to when this in/out gauge was installed. quite some km's ago.

I just don't see it as an acceptably efficient unit - never have.

I'd have to be considering a bar and plate design for the potential of running at 20 psi boost reliably with (at the every least) extruded header tanks with the ideal having turbulators to reduce the liklihood of laminar flow......in an ideal world. Thus we have the engineering dichotomy - turbulators increase resistance to flow but in turn increase heat exchange between the Al and the air........I'd rather lose some boost (as I NEVER EVER run above 2500 rpm) so flow efficiency isn't so critical as increasing the density of my air charge.....which is poor in these units by my measurements.

Cheers

Interesting point

Because, with a VNT such as the 05 and 06 Liberty CRD, boost is controlled by to ECM as sensed by MAP sensor. So in reality, no boost is lost because the ECM, sensing lower boost, would demand more from the turbo.
So, if flow efficiency is lost but cooler intake air is gained, then that sounds like a win.
The downside is that the turbo will be forced to work a little harder.

_________________
U.S. Army Retired

I am not sure if this is what you were saying, but the charts above are for the stock and aftermarket cac's from the BMW 3L turbo motor, not ours.

I dont know if I buy that a lower flowing(turbulators), high cooling efficiency CAC is the answer. The reasoning is that the ECU is going to force the turbo to generate the same boost within the Intake manifold regardless of the flow characteristics of the CAC. If you are cooling the air a tremendous amount, but at the cost of high resistance, then suddenly you have a much greater mass flow rate entering the cylinders at the same pressure as the stock CAC. The consequence is that the Turbo now has to work harder, and at higher boost levels on the hot side of the CAC, to provide the required mass flow rate which means more power is needed to spin the turbo and the air entering the CAC is hotter. That may work against you from an efficiency standpoint, and without retuning, you will make no power gains as the ECU is only going to inject a set amount of fuel anyways since it does not care about AFR.

The air going in and out of the CAC has to make a lot of right angle turns and is moving at a pretty fast rate. I had my CAC hose off the other day while I was taking some compressor rpm readings and it was spitting air out like a leaf blower at idle. I cannot imagine that it would be laminar through the CAC with the exception of off throttle conditions. I think given a much larger, higher flowing CAC, we could see some improved MPG's under load and increased horsepower through efficiency gains alone.

I guess now that I have thought about it I think the following:

-For peak power you want the a CAC maximum cooling capabilities along with tuning to add the extra fuel that you can now burn thanks to the higher mass air flow.
-For peak efficiency you need a CAC with the least resistance and reasonable cooling to reduce the turbos effort. As long as you keep the mass flow rate the same as what the ECU expects, the engine will need to provide less work to gain the boost it wants while still burning the fuel that is injected. since a diesel can run at very high afr's, you could be cruising along at 70mph, using only a little fuel but still pumping 15+ psi.

_________________
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

My numbers prove we are better than that. What's your basis for disputing it? Where does your 1% efficiency number come from?




I'm not sure why you're talking about RH when it has little effect on cooling something that's not wet to begin with. Please take some measurements like I did and use the same industry accepted standard formula so we can compare.

As for why you're not seeing much of a temperature drop, you already identified it - your AC was on. That gives much hotter air off the condenser and entering your cooling stack. i.e. you can't expect 150F ambient air to cool off the 150F charge.

I have no idea what the pressure drop of our cooler is - I was only measuring thermal efficiency.

_________________
05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.

Just a quick response.
That was harsh and unesecesarily critical of a long-term observation of real-world information.
I will just not waste the time and share real numbers I have observed over a long period.
I actually don't have the time to waste on the unappreciative anyway.
I am at the point where the negativity of most just wants me to keep more and more to myself especially when people don;t read what I have actually written and then jump.

I used the the same formula catcrd used. Where does it say you have to have false running conditions?I did note this.

WHOA!
I mention Relative Humidity because it has much to do with the ability of air to carry heat with it.
This system has a high entropy (the bit which doesn't do work) Unfortunately it should be high.
Thus RH is highly relevant in terms of heat exchange ability of external cooling air.

The MAP is superfluous when measuring temperature IN THIS CASE. Yes, it influences combustion control but where/how does THIS system measure aftercooler efficiency? That is a separate issue. This engine is scant on sensors at best.

MAP temp sensing is irrelevant other than for controlling factors beyond those we are writing of. Please don't give them more cred than they deserve. but by the same token RH does influence manifild absolute PRESSURE by affecting the density of the air.
MAP runs the engine - not measures the efficiency of the aftercooler.

I thought the issue was;
How would the system perform with a more efficient heat exchanger????

Why not look at real world situations? rhetorical.....
Rhetorically (cos I don't give a rats about the answer) is it being suggested I drive around in utterly sweltering temperatures (constantly) to appease some.
Until complete methodolgoy and engine loading etc is standardised other than an approximation of grade this is a pointless jab. At least I had real world engine loads. This cannot be replicated unless RH and the other misunderstood factors are stated with a degree of certainty. I at least measured these environmental parameters which do affect the system.

I again draw attention to the fact that this is a long-term (for some 6 years) observation of the inefficient operation of this aftercooler.
-Initially based this on Performance How-To Turbo. Real World High Performance Turbocharger Systems by Jay K Miller.-
ISBN-13 978-1-932494-29-7
For now, simple fact is that temp IN often is NOT sufficiently /significantly less than temp out in the CAC for normal everyday benefit which suggests that in REAL WORLD running it is an inefficient unit.
Therefore, the heat exchange efficiency of the unit is POOR.

I have watched this behaviour constantly for 6 years. It doesn't change.
This aftercooler is consistently POOR at creating a TEMPERATURE DIFFERENTIAL (in the right direction) that my reading from fact checked texts tells me is acceptable.

The CAC is (again read from the source above which is a nice basic presentation) without even mentioning the Laws of Chemical Thermodynamics.
Air is a complex thing and clearly misunderstood.
It took thousands of years to even get to Boyles law let alone the more sublime nuances of its behaviours.
It is a study in its own right.

WHY Relative Humidity (RH)?
Its behaviour is governed by P, T and mass. It has nothing to do with dealing with a wet surface.
It is to do with heat capacity.
100% saturated air (common where I live) has Specific Heat (Cp) of 2000 Joules / Kg deg K
and cold air by the same token has Cp = 1020 Joules /kg deg K
In other words:

The mean molecular weight of dry air is approximately 28.97.

The molecular weight of water is only 18.

This means that volume by volume, moist air is lighter than dry air.

The amount of energy required to heat up dry air is less than the amount to heat up the same volume of wet air. This is because of the difference in Specific Heat between dry air and water vapour.

Everything has a Specific Heat. This is the amount of energy that is required to heat up a given mass of stuff compared to the amount of energy required to heat up the same mass of pure water. If we keep the pressure the same, the Specific Heat is termed Cp.

Cp for 100% water saturated air at atmospheric pressure is about 2000 Joules/kg deg K (or 2.00 kJ/kg deg K)

Cp for dry air at atmospheric pressure is 1020 Joules/kg deg K (or 1.02 kJ/kg deg K)

Integral to the CAC design is a trade off between the heat exchanged within the unit and radiated to the outside environment (hence, the mention of turbulators). All engineering is a trade-off when it comes to heat exchange.
I would also suggest some folk look at the behaviour of non-ideal gases.

The fundamental premise that is being missed is that turbulators increase the density of the air exiting the Aftercooler. Therefore they have the potential to increase efficiency. This is, afterall, the primary function of an aftercooler is to further increase the density of air after the turbocharger has done its work. (Miller). Again per Miller the gas laws dictate a loss of 1 to 2 lbs across the aftercooler.

Quote (Miller)....which I happen to agree with by qualifications....."An aftercooler, by its very nature tends to be somewhat of an engineering dichotomy. It is both a pressure vessel and a heat exchanger.

Miller then runs into a rather useful description of available designs that are best suited for boost of around 20psi...which I again concur with. For the unitiated he describes the difficulties in encountering laminar flow in an aftercooler and how (loosely) it introduces certain ineffiencies of design of heat exchangers and then reviews (convincingly) the gains of turbulators. The mistake being made is that efficient flow with little resistance is the absolute goal. Fact: without contact with the metallic interface with the outside air ram there is minimal heat exchanged.
Air is not an ideal gas since it is not pure.

Seems to me some very basic engineering and physics needs to be better understood before I get shot at and some credibility assumed for long-term as opposed to short term observations.

That is all I have to say on the matter.

For all the numbers and claims of intercooler efficiency, how does the Liberty CRD intercooler compare to other turbo charged engines?

_________________
U.S. Army Retired

I can try and datalog on my EcoBoost F150 soon. I believe that has IAT sensors pre and post CAC as well as an ambient temp sensor so it should get some good data.

_________________
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

Here's an aftermarket intercooler with an OEM application that may be worth considering:

http://www.ebay.com/itm/252253496692?_t ... EBIDX%3AIT

This intercooler is used in the 1999-2003 Isuzu NPR with 4.8L diesel engine. I have an Isuzu OEM version made by Tokyo Radiator. The core is 20 x 14 x 2. The distance between the inlet outlet tubes matches the reliefs in the top of the CRD radiator tanks. (I checked it against an old CRD radiator that I have.) The inlet and outlet tubes are 2-3/4 inch OD. The inlet and outlet tubes will require replacement and proper angle adjustment to match the CRD intercooler. The Tokyo Radiator unit is extremely well built and appears to be an efficient design. I do not know if this aftermarket version has the same fin count as the Isuzu.

At $223, it may a good starting point as a replacement for the CRD intercooler.

_________________
2006 CRD Sport
GDE FT ECO tune, GDE TCM ECO tune, ARP studs, HDS-001 203F T-Stat, 3.7L nylon fan & Hayden 2905 clutch, Carter P76148M in-tank pump, Racor 245R122 filter head & 2 micron R25S fuel filter, Provent 200, Samcos, Fumoto F-102, Litens 920834A de-coupler, PML rear diff cover, OEM trans pan with welded in bung, JBA UCAs, full skids.

At $223.00 you can't beat that price.

_________________
2005 Jeep Liberty CRD Limited
Build Date May '05
OME lift kit
Samco hoses
Weeks Stage 1
PMF EGR plug kit
ARP Stud
Cracked CAC repaired with epoxy filler