With the recent discussion about bigger intercoolers I decided to take some data to see what our intake temps were like pre and post cac and whether the intercooler is doing its job well. I used 2 fluke 87s with thermocouples reaching inside the cac hoses and did some highway testing. These meters can display instant/min/max/avg data.

I correlated the two meters to each other and to the EVIC temp first by tying the thermocouples in the grille and driving around town. The three readings were within 2 degrees of each other at steady state, so I didn't include any offsets in these readings below. Then I inserted the probe wires into the cac hoses under the hose clamps.

Ambient temps hovered around 70F throughout the test, humidity around 50%, no A/C, rain was not a factor, elevation 5000ft. All temps reported in ºF.

I don't have boost/egt gages (yet) - that would've been great data to have. I did some testing up the same long grade at 65mph between 3rd gear w/ lockup and 5th gear w/lockup to see the temeperature difference. 3rd gear had higher post cac temps by 5-10 degrees because the higher volumetric flow rate was starting to ovewhelm the cac, but I can't say if that was achieved with lower boost or egt than in 5th gear. Other people with those gages could comment.









I usually run with a bug screen over the grille, but I did my testing without it for the data above. I found that adding the bug screen at the end raised post cac temps by 5-10 degrees.

The highest temps I saw were while accelerating up the 10% grade. I took the reading as the temps seemed to stabilize. A nozzle to spray water/meth across the front of the intercooler would have been interesting.

The formula for thermal efficiency of an intercooler is

E = (Tin -Tout)/(Tin-Tambient)
At 40mph cruise we are at 89%
At 65mph cruise we are at 81%.
At full load we are at 67%.

Feel free to discuss. If you have any interesting ideas for temps to measure, let me know. These probes only have a rating of about 500F, hence no EGT. I could go down the tranny dipstick tube, but others have reported trans temp before. Maybe oil temp is possible, but I don't know about putting a wire down into the oil dipstick tube!

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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.

How about you remove your intercooler, clean it, and retest?

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http://www.Colorado4Wheel.com
"Its not about what you can DO with your Jeep, its about where you can GO with your Jeep."
Knowledgeable - But Caustic

Sam.

When I had my jetta TDI some were using dish washing detergent and filling the intercooler with water in place just removing the hoses. Of course being carefull to remove all water. Would that be an effective methode on our CRD's?

Never mine! Both hoses are on the top so it would be impossable to drain it

Joe

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)

do it right and remove it. You don't want to leave any detergent in there.

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2005 Liberty CRD
235/75R16 Firestone Destination's, Fumoto Valve
Boiler's Aluminum Roof Rack

Anyone considered a pressure test on the CAC to see if there is much of a drop in 15 seconds to see if the turbo is having to work harder to keep pressure up? CAC pressure loss would cause decrease in mpg as well.

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Environmentalist Green + Socialist Red = Facist Brown

2006 Liberty CRD, Frankenlift II, Al's A Arms, Moog LBJ's, GDE tune, Etechno GX3123 Glow plugs, Fumoto drain valve, Elephant hose CCV mod.

Not being a gear head, or engineer I have no idea what the % of thermal effeciency really means. I assume that there must be some "standard" for comparison or some way of comparing our jeep's results to those of similar type engines. So, what I am asking is what does the test show: good or bad results? 69% seems low, but I have no foundation for comparison.

Good tests - more with comparison ac on\ac off - type J tc's will indicate to over 1800*F - type K has wider range, is usually used for engine

For those with scantools, oil temp, water temp, fuel temp, intake air temp, intake manifold air temp are all available - only compressor out and EGT is lacking

Generally speaking, only time you'll see ambient out is idling - any temp rise there is ac condenser and underhood heat - outlet temps within 30* of ambient is considered efficient, incl smaller vehicles with little frontal area - only the big-rigs have enuff real estate for a cac without an ac condenser crammed in front of it - only way to improve this is water-air, or spray-misting, as mentioned, incl injection-misting - but then you need reservoirs for the liquids, + you need to constantly maintain the ph levels in the H20 tanks - easiest method to reduce cac outlet temps with out costing a bunch is turn off the ac

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'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

I would like to take my intercooler out and clean it, but I stopped at the step in the service manual where it said to purge the A/C lines. I didn't try to find a workaround for that and was not that interested at the time.

Fluke specifies a 500ºF ceiling for these probes, so that's what I stuck to.

80+ % efficiency is pretty good, but at full load the system is lacking a little. Not a bad tradeoff though, since little time is spent there.

At 300+ degree output temps it's no wonder DC redesigned the hot side hose.

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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.

That 500* ceiling could be due to the probe construction, incl sheathing material such as plastics, so it's prolly wise to heed the suggestion

FYI: you can pick up new hi-temp type K probes from Omega for ~16 bucks, same probes most vendors use in their pyrometer sets -

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'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

I didn't know oil temp was visible to scan tools.

As far as I know trans temp isn't, even though we have an idiot light for it.

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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.