Stock Exhaust Gas Temperature

retmil46 · **Posted:** Sat Dec 10, 2005 1:10 am

I called TST Products today, asking if they could tell me what they were seeing for Exhaust Gas Temps on a stock CRD without any mods.

They said that during normal highway driving they were seeing EGT's well over 1000 degrees. This was measured at the manifold, prior to the turbo. They said that the EGT heated up fairly quickly, and took quite a while to cool down after driving.

Sounds like it might be a good idea to follow the cooldown table in the owners manual. :shock:

I know several people are already running performance modules on their CRD's. It might be a wise idea to invest in an EGT gauge to monitor what's going on when you call on that extra power.

1300 degrees and above is where bad things start to happen to turbochargers and exhaust systems. If the stock setup is already running over 1000 during normal driving, that doesn't leave a whole lotta elbow room. And one of these performance modules, cranking an extra 50 hp or so out of that engine, could easily push temps past this point.

Ranger1 · **Joined:** Mon Oct 17, 2005 7:40 pm **Posts:** 1137

When I emailed them a while back, they sent me some temps that went as high as 1300 F at full power on the dyno. Idle after a run was somewhere around 750-900 and 60 mph was close to 1000 F. I assumed it was with their tuner box installed. Man, if the turbo is seeing 1000 stock and 1300 WOT, a tuner sounds like bad news for the CRD turbo.

I looked at a TDR article on their testing of most of the diesel tuners available. They seem to be available in two basic designs - overfuelers and pressure boosters. Some apparently do both. The bad news looks like overfuelers raise EGT's that are normally around 975 to the 1350 range. Pressure boosters do better. Some advance the timing and do even better. I'm not crazy about boosting rail pressure, it just doesn't seem like a good idea for the pump and injectors health.

What I'm wondering is how the CRD will do with an overfueler like DieselTuning sells? If it runs 1000 F stock, 1300 WOT stock, it would seem an overfueler tuner is almost certain death in summertime temperatures. I asked DieselTuning if they had any EGT's for the CRD and they said no, due to the the CRD being very hard to find in Canada.

I'm rethinking this idea until I see some dyno charts and egt's (in summertime temps, not 50F outside temps) under cruising and WOT from these companies. I think by not providing this information they might be leaving out some vital information.

retmil46 · **Posted:** Sat Dec 10, 2005 1:24 pm

Yes, it looks as though DC is pushing the limits, running high stock EGT's to get as small a turbo as possible so they could fit this beast under the hood.

On the other thread I started, about TST Products, there's a link to the installation instructions for their '03-'04 Dodge Cummins module. By way of comparison, under the section for setting the EGT limits on the module, they say that at 75 mph highway with an unloaded vehicle the Cummins EGT runs in the 600 to 800 range with a stock setup.

It's no bloody wonder this thing warms up so fast after you start driving it. The EGR system is dumping some serious heat into the cooling system. Even if you don't plan on towing anything, sounds like it would be worthwhile to get the towing package when you buy one just for the extra cooling capacity.

In the TDR article, according to their graph, the modules that ran the hottest were the overfuelers and the pressure-only boxes. The modules that ran the coolest were the ones that did pressure and timing, and the TST module that did timing and duration. Looks like the key is timing adjustment.

And airflow management!!! Whatever you could do to make this beast breathe better and lower the stock temps before adding any of the strap-on electronics. A high flow air filter (as long as it doesn't compromise dirt filtration) and a high flow exhaust or muffler.

Some of the higher end modules have a display with EGT monitoring, and an EGT limit function built in. You can program what temp limit you want, and if it senses that you've reached or exceeded this limit, will back off to stock settings until temps come back down. For the CRD, sounds like that feature would be worth the extra money.

I wouldn't be too discouraged. These beasts have been out less than a year, and the aftermarket guys are just getting started developing products for them. As popular as they seem to be getting, in the long run I don't think we'll be lacking for goodies - the more popular a vehicle is, the more aftermarket players that will make applications for it. For now we just have to be patient and bide our time.

oldnavy · **Posted:** Sun Dec 11, 2005 9:03 am

The aftermarket aircleaner's will do little for EGT's and only increase dirt in engine oil, we went through all that testing several years ago on the TDI Club Forum. The removal of the muffler and adding a straight through muffler or a straight pipe reduced the EGT's on the TDI VW's by 20 to 30% and is why I went with no muffler when I upgraded to the big injectors, tweaked the timing, IQ and a few other VAG-COM tricks, along with Stage II RC.

I was going to go with straignt pipe replacement or a straight through steel packed muffler from local muffler shop, but may consider Aero-Turbine, with the idea to drop EGT's and aid spool up of the turbo. The thing I don't like about the Aero Turbine over the other two options is the price, I can have a straight pipe done for about $30 or a Steel pack straight through muffler for $80 installed.

The reason the CRD warms up so fast is the viscous heater installed within the cooling system, not the turbo EGT's. The viscous heater will allow for long idle periods without fuel wash down caused when engine cools down so far as to not allow complete fuel combustion. I have let the CRD idle in 10*F weather for 15 minutes with only a 10* drop in engine temp and a 30 minute idle in upper 20's F temp with only a 5*F drop in the temp of the coolant. I've seen the VW TDI go from 190*F to 110*F within less then two minutes at idle. With a 1500W tank heater in the coolant line the TDI would drop from 180*F to 140* within 30 seconds of starting and would take about 3 miles before the temp got back to normal 190*F operating temp. The CRD warms up so fast that I haven't driven my Magnum in the mornings since the weather got so cold, the magnum doesn't warm up as fast as the CRD.

retmil46 · **Posted:** Sun Dec 11, 2005 12:42 pm

oldnavy wrote:

The aftermarket aircleaner's will do little for EGT's and only increase dirt in engine oil, we went through all that testing several years ago on the TDI Club Forum. The removal of the muffler and adding a straight through muffler or a straight pipe reduced the EGT's on the TDI VW's by 20 to 30% and is why I went with no muffler when I upgraded to the big injectors, tweaked the timing, IQ and a few other VAG-COM tricks, along with Stage II RC.

I was going to go with straignt pipe replacement or a straight through steel packed muffler from local muffler shop, but may consider Aero-Turbine, with the idea to drop EGT's and aid spool up of the turbo. The thing I don't like about the Aero Turbine over the other two options is the price, I can have a straight pipe done for about $30 or a Steel pack straight through muffler for $80 installed.

The reason the CRD warms up so fast is the viscous heater installed within the cooling system, not the turbo EGT's. The viscous heater will allow for long idle periods without fuel wash down caused when engine cools down so far as to not allow complete fuel combustion. I have let the CRD idle in 10*F weather for 15 minutes with only a 10* drop in engine temp and a 30 minute idle in upper 20's F temp with only a 5*F drop in the temp of the coolant. I've seen the VW TDI go from 190*F to 110*F within less then two minutes at idle. With a 1500W tank heater in the coolant line the TDI would drop from 180*F to 140* within 30 seconds of starting and would take about 3 miles before the temp got back to normal 190*F operating temp. The CRD warms up so fast that I haven't driven my Magnum in the mornings since the weather got so cold, the magnum doesn't warm up as fast as the CRD.

Ok, I'll plead ignorance. What are you referring to when you mention the "viscous heater"? Do you mean that besides the 120VAC block heater that you plug into a wall outlet, there's a 12V heater installed in the coolant system also, that kicks in when you start up to help raise temps?

I ordered the service manual CD and wiring diagrams from DC on techauthority.com 2 days ago, I wanted to learn how this beast ticked.

When I mentioned the EGR system dumping heat into the cooling system, I was in part assuming that this engine has a cooled EGR system, like the large Detroit's at work, where the recirced gas is run thru a cooler tied into the coolant system, to reduce temperature prior to feeding it back into the intake. TST mentioned that the EGT rose very quickly once you put a load on the engine, and that it took a good while for it to cool down once parked. With 1000 degree EGT's during normal driving, it seemed logical that they would use an exhaust gas cooler.

You wouldn't happen to know what the TDI's run at for EGT would you? Might be interesting to compare the two.

Uh oh, just had another idea for more gauges - air temp at the inlet and outlet of the intercooler, to see how effective it is.

Regardless of whether it's the viscous heater, cooled EGR, or heat dumped into the engine cooling jacket, it just seems that exhaust temps this high would be part of the reason the CRD warms up so quickly once driven.

retmil46 · **Posted:** Sun Dec 11, 2005 1:36 pm

oldnavy wrote:

The aftermarket aircleaner's will do little for EGT's and only increase dirt in engine oil, we went through all that testing several years ago on the TDI Club Forum. The removal of the muffler and adding a straight through muffler or a straight pipe reduced the EGT's on the TDI VW's by 20 to 30% and is why I went with no muffler when I upgraded to the big injectors, tweaked the timing, IQ and a few other VAG-COM tricks, along with Stage II RC.

Agreed. Personally, I was surprised that everyone jumped on the AFE Proguard bandwagon so quickly. I mentioned it so that people determined to try something like this would at least know there was something out there several orders of magnitude better than a K&N.

On the GM Duramax filter test you linked to, the AFE filter with the 73-XXXX part number is probably a Proguard 7 filter. From their part number index, all the Proguard 7 filters look to start with a 73 prefix.

Looking at the numbers, it did surprisingly well for a high flow reuseable filter. The one category where it really fell on it's face was how long it took to clog up, and the amount of dirt it took to do that. While on the one hand that's good news, it's actually stopping dirt, unless you were religious about keeping it clean you'd soon be worse off than with a stock filter. And it still passed 5 times as much dirt as an AC Delco.

By comparison, the AC Delco went for 3 times as long (60 minutes) and stopped 573 grams of dirt before it met their criteria (10" H20 differential) for being clogged. 573 grams is over a POUND of dirt, over half a kilo! And it only passed 4 tenths of 1 gram of dirt.

The AFE filter looks like a decent compromise filter, really designed for the Cummins and Powerstroke crowd that ARE working their engines hard, pulling heavy trailers and seeing high intake air flows, but still needing decent filtration. I called my friend in Texas, and repeated the one comment on the test, about when we were actually going to see 350 cfm intake air flows. He immediately shot back "My Cummins whenever I pull my toyhauler trailer".

For most people, who install an air filter and forget about it for the next 10,000 miles, and are just doing normal highway commuting, the AC Delco would seem to be the best choice.

oldnavy · **Posted:** Sun Dec 11, 2005 1:40 pm

Sorry I went back a looked and you had EGR and I had been reading EGT's and just read it as such, my bag. You are probably correct on that one, I would think it would help some, maybe not a whole lot, but some.

I am assuming they run the viscus heater by mechanical means. It's a heater using a special fluid that is put through a shearing process (as through gears) that heats this fluid quickly and then as the main coolant circulates over the viscous coils it adds heat to the coolant. That was a very simple explanation. The link above states for Euro models only, but I'm told the US & Canada CRD's have it also. That must be why we warm up fast and loose very little heat on very cold days at idle.

oldnavy · **Posted:** Sun Dec 11, 2005 1:52 pm

retmil46 wrote:

oldnavy wrote:

The aftermarket aircleaner's will do little for EGT's and only increase dirt in engine oil, we went through all that testing several years ago on the TDI Club Forum. The removal of the muffler and adding a straight through muffler or a straight pipe reduced the EGT's on the TDI VW's by 20 to 30% and is why I went with no muffler when I upgraded to the big injectors, tweaked the timing, IQ and a few other VAG-COM tricks, along with Stage II RC.

Agreed. Personally, I was surprised that everyone jumped on the AFE Proguard bandwagon so quickly. I mentioned it so that people determined to try something like this would at least know there was something out there several orders of magnitude better than a K&N.

On the GM Duramax filter test you linked to, the AFE filter with the 73-XXXX part number is probably a Proguard 7 filter. From their part number index, all the Proguard 7 filters look to start with a 73 prefix.

Looking at the numbers, it did surprisingly well for a high flow reuseable filter. The one category where it really fell on it's face was how long it took to clog up, and the amount of dirt it took to do that. While on the one hand that's good news, it's actually stopping dirt, unless you were religious about keeping it clean you'd soon be worse off than with a stock filter. And it still passed 5 times as much dirt as an AC Delco.

By comparison, the AC Delco went for 3 times as long (60 minutes) and stopped 573 grams of dirt before it met their criteria (10" H20 differential) for being clogged. 573 grams is over a POUND of dirt, over half a kilo! And it only passed 4 tenths of 1 gram of dirt.

The AFE filter looks like a decent compromise filter, really designed for the Cummins and Powerstroke crowd that ARE working their engines hard, pulling heavy trailers and seeing high intake air flows, but still needing decent filtration. I called my friend in Texas, and repeated the one comment on the test, about when we were actually going to see 350 cfm intake air flows. He immediately shot back "My Cummins whenever I pull my toyhauler trailer".

For most people, who install an air filter and forget about it for the next 10,000 miles, and are just doing normal highway commuting, the AC Delco would seem to be the best choice.

I have never ceased to be amazed at the people who will use the K&N type filters, even after reading test results of oil samples and now the Duramax test. I figured that if these folks wanted to use that type of filter then I would point them to about the best one on the market.

Myself I am waiting for the Ne Nanofiber filter to become available and they will be available from Aimsoil dealers.

I have a friend with a EGT gage installed on a stock Jetta TDI 5spd manual tranny car, I will email him and ask. I will post it here when he emails me back, my guess/feeble memory was 800* to 900* for stock engine.

Ranger1 · **Joined:** Mon Oct 17, 2005 7:40 pm **Posts:** 1137

TST mentioned that they felt the over-aggressive use of EGR on the Liberty CRD was the prime reason that the egt's were so high. It's my guess that this was the only way DCX was able to get it to pass Tier 2, bin 10 emissions. There really isn't any other reason for a diesel to run temps this high. I also read once where EGR can add nearly 40% heat load to the coolant system. All in the name of NOx reduction, while every weekend, with most of the big rig diesels off the road, NOx levels increase instead of decreasing, to the point where this effect is called the "weekend effect" in one study. EPA and CARB remain silent on this study, as it contradicts the basis for their NOx policy. Meanwhile, hybrid's continue to pollute with non EPA regulated, but still toxic exhaust gases, with the full consent of environmentalists, educated with sound-bite level science. God bless their one-track minds.

This is a good example of an engineering compromise brought on by bad science twisted into bad policy. Euro III and IV focus on CO2, and phase in NOx reduction as the technology is developing. US emissions policy is so political in nature and misinformed that we end up with 1000 F cruising egt's. I've seen the mpg figures on 2 identical cars, the Mercedes E320 CDI, with the inline 6, identical in every way except emissions - the one with Euro III was rated ~ 34 mpg, the other, for Euro IV, 30 mpg. Euro IV is still better than whats waiting for the U.S in 2007, with tier 2, bin 5. God knows how much loss of mileage, loss of longetivity it will add to diesel engine systems.

The viscous heater is on the passenger side of the engine, visible without taking off the engine cover. It looks and acts like an AC clutch, cycling on and off. It looks like clever design, with a built-in heat exchanger, connected directly to the heater core, than back to the engine block, heating up the cab, then the engine first when cold weather is plentiful. The EGR heat induced problem starts after the engine warms up, heating up both the intake air and engine coolant, as it is water cooled.

retmil46, I'm am really looking forward to see what the results of your pyrometer and new muffler. It occurs to me that we have not seen anyone yet independently verify the EGT's our CRD's running stock. If you use a dealer to install both the muffler and pyrometer, I'd be interested in knowing if they try to talk you out of the pyrometer. It would enable you to verify their claim of egt reduction...

retmil46 · **Posted:** Sun Dec 11, 2005 5:01 pm

oldnavy wrote:

I was going to go with straignt pipe replacement or a straight through steel packed muffler from local muffler shop, but may consider Aero-Turbine, with the idea to drop EGT's and aid spool up of the turbo. The thing I don't like about the Aero Turbine over the other two options is the price, I can have a straight pipe done for about $30 or a Steel pack straight through muffler for $80 installed.

Yeah, that price is pretty hefty. I'd considered a straight pipe myself, but didn't know how the local cops would react to the noise and the local inspection stations would react to the complete lack of a muffler. They've gotten pretty anal in the last few years around here, particularly making sure the licensed stations do a full inspection and not let anything slide. Only 3 stations within a 10 mile radius still have a license to do inspections, all the rest got theirs yanked by the state for fudging on them.

I'd considered the glass pack route also, but the local places all carry the cheap aluminum versions and I wasn't impressed with their looks. Guy at one place actually told me I wouldn't lower EGT's with a straight thru muffler, that I'd get a check engine light and end up burning up valves and glow plugs due to the lack of back pressure, and was trying to get me real hard to buy a Flowmaster. I left that place in a hurry with a firm hold on my wallet! And I don't feel like buying a pig in the poke thru JC Whitney either.

There's actually an Aero Turbine dealer in town. I went by there, and they had one on display, a 3" version, cut away so you could see the inside. Nothing wimpy about it, heavy gauge stainless steel and quality construction, good quality welding on the internals. I could believe their flyer when they said no-conditions lifetime warranty.

Other reason I'm considering the AT, we've already had someone, albeit on another list, that has tried one and reported back on it.

retmil46 · **Posted:** Sun Dec 11, 2005 5:23 pm

One thing that has made me pause for reflection when considering the AT muffler, is this catalytic converter dependent on these high temps to work? If we end up reducing the EGT, would the cat become ineffective and cause the vehicle to fail emissions testing if they do actual tailpipe monitoring, instead of just plugging in to the onboard OBDII computer?

They had an actual setup of an EPA '07 Detroit Diesel in the plant last week. My gawd, what a huge cat! 3 feet long, 1 1/2 feet in diameter, 4" inlet and outlet, and weighed over 300 pounds! They're going to have to install a separate crane on the chassis line just to lift these converters into the frame rails.

As far as the rest of the engine, there were so many new controls added on, it's going to be a nightmare bolting those things together. The intake and EGR setup looks like a giant version of what's on our CRD's.

Ranger1 · **Joined:** Mon Oct 17, 2005 7:40 pm **Posts:** 1137

"If we end up reducing the EGT, would the cat become ineffective and cause the vehicle to fail emissions testing if they do actual tailpipe monitoring, instead of just plugging in to the onboard OBDII computer? "

A risk I'm willing to take if it lowers egt's a few hundred degrees.... however, in my state, if you have a diesel, they don't even check the emissions... surprised me, all they check is the lights, wipers, brakes, horn and tires.

However, if worst comes to worst, and a tailpipe diesel emissions does come in, I notice there isn't any sensor on or near the CRD cat as there is on the V6 Libby. This means the ECM can't tell if the catalyst is working, although a tailpipe check could. If these mufflers work out and reduce CRD egt's, maybe a Y pipe could be installed, with the original muffler on one side, the new smaller muffler on the other - switch a cutout muffler valve for emissions check, warm it up and you're off! Switch back to the AT muffler for normal, non turbo destroying egt's for the other 364 days of the year. A little drastic, but certainly less than a new turbo, or worse, an engine rebuild if a turbo melts down.

oldnavy · **Posted:** Sun Dec 11, 2005 6:33 pm

The cat should not be affected by the muffler removal as close as it is to the turbo, never was on the TDI's either. I check with couple of TDI guys and their VW's run 600*F to 800*F in the 70 to 80 mph range stock or chipped and only have 1000* on stock engines when pushed to max. The Chipped and big injectors equipped cars can run 1300 to 1450 when driven above 90 mph or with 0 to 110+ runs.

If ours are running 1000*F at 70 to 75 mph then no wonder the turbo has so much open area around the thing. I remember that the main reason for taking the mufflers off the TDI was to drop EGT's on the chipped cars, and best I remember it dropped the tems back about 200*F at 70 mph. At the time I had my heavy modded TDI NB I didn't have the EGT gage but others did and they reported drops of 150*F to 250*F on their turbo's.

Mitch the turbo is/was considered a legal muffler in the US and some on the big rigs come with it stamped on the turbo. You may want to research that for use there in VA. That's not to say they haven't changed the laws, but I remember looking it up before I took my NB in for inspection in 01 at local dodge dealership. The inspector new of the law (he had just come from working at a Cat dealer/OTR Truck center) and said nothing about the muffler. Later when I ask about muffler requirements on diesels he said there was none for a turbo diesel, only gas engines.

Forgot but the last I heard no state had an exhust test for diesels, and none of the guys with old MB's with diesel's at 200k miles failed. One TDI guy had his EGR removed even, but was running B100. When some guy tried to check a TDI forum members car in NY the car passed with no Cat, no muffler and was running home brew Biodiesel about 3 years ago.

Ranger1 · **Joined:** Mon Oct 17, 2005 7:40 pm **Posts:** 1137

This disucssion has convinced me to look into getting a pyrometer installed.... I'll start looking around to see what I can find. The gauge is the only problem for the libby I can see. Not a lot of good places to permanently install another gauge. I've been wondering if you install one yourself how to keep the drilled metal shavings from getting into the turbine when you drill the housing. Anyone have any experience on how to do this? If some metal shavings do get into the turbine blades, is it a problem?

oldnavy · **Posted:** Sun Dec 11, 2005 7:29 pm

Ranger1 wrote:

This disucssion has convinced me to look into getting a pyrometer installed.... I'll start looking around to see what I can find. The gauge is the only problem for the libby I can see. Not a lot of good places to permanently install another gauge. I've been wondering if you install one yourself how to keep the drilled metal shavings from getting into the turbine when you drill the housing. Anyone have any experience on how to do this? If some metal shavings do get into the turbine blades, is it a problem?

Just put heavy grease on the drill bit and tap and when you first start the engine let it idle a minute or two so any chips would blow on past. This is done all the time and has never caused a problem that I know of, just take your time.

greiswig · **Posted:** Sun Dec 11, 2005 9:14 pm

[quote="Ranger1"]When I emailed them a while back, they sent me some temps that went as high as 1300 F at full power on the dyno. Idle after a run was somewhere around 750-900 and 60 mph was close to 1000 F. I assumed it was with their tuner box installed. Man, if the turbo is seeing 1000 stock and 1300 WOT, a tuner sounds like bad news for the CRD turbo.

Those are pretty high temperatures, it seems to me. On my Mercedes OM-352 engine, I see temperatures as high as 1350F at some engine RPM's without a turbo. I back off on the go-pedal when it hits that. For a long time, 1250F was the "max permissible" in the Unimog community, but I did some research on bone-stock vehicles and found that, since they do not come equipped with an EGT guage, many of these engines were commonly running temperatures well over that number for extended periods.

When you turbocharge those engines, the EGT's come way down...a few hundred degrees.

I assume that the EGR valve is operated by a vacuum line on our CRD's, so it should be quite simple to disconnect the EGR long enough to find out whether this is making the EGT's go up. Anyone done that?

Ranger1 · **Joined:** Mon Oct 17, 2005 7:40 pm **Posts:** 1137

CRD egr valve is electric. It can be disconnected, but its so far down on the driver side near the firewall that its a pain to get to. It also sets a code if you disconnect it. Worth trying if you have a pyrometer installed, just to see the difference, as long as it doesn't force you into limp in mode.

oldnavy · **Posted:** Sun Dec 11, 2005 9:28 pm

Ranger1 wrote:

CRD egr valve is electric. It can be disconnected, but its so far down on the driver side near the firewall that its a pain to get to. It also sets a code if you disconnect it. Worth trying if you have a pyrometer installed, just to see the difference, as long as it doesn't force you into limp in mode.

Hummm I have a ScanGage wonder if I clear the code it would stay cleared? Wife is off starting next Friday till after New Years when school starts back, so I should have some time to check that out. I thought I remembered seeing the electrical connector for EGR on top, must have been a senior moment.

retmil46 · **Posted:** Mon Dec 12, 2005 12:10 am

I called the main regional warehouse in Hickory for AT, and the guy there actually ENCOURAGED me to install a pyro and get some before and after data, in part so he could have some hard numbers to quote for other potential CRD buyers. Gentleman had that much confidence in his product.

As long as the parts at work aren't "per serial" (designated only for specific trucks by serial number) and are generally stocked, we can purchase most anything that goes on one of the semis for what it cost the company to buy them. I priced a pyrometer setup from one truck. An Ametek 300 - 1500 degree 2" pyrometer gauge would be $42, the thermocouple would be $25, jumper harness $11. Before you get any ideas about a group buy, this is for employees only, people who have bought up quantities of items and resold them on the side, whether or not they made a profit and regardless of their intentions, have ended up losing their jobs. I'd say anything more than a quantity of 3 to 5 would start raising questions.

Also, they use rather large thermocouples. They require a 1/4" NPTF hole for mounting in the manifold or exhaust pipe, and stick 2 1/2" into the manifold/exhaust. Nearly all of the aftermarket pyros/monitors I've seen use a 1/8" NPTF hole.

However, even getting just the gauge itself would be a substantial cost reduction, most of the aftermarket pyro setups go for 150 to 250 bucks. As long as you could find the correct type thermocouple that would work with it, in 1/8" NPTF and a length we could use, these gauges would work. Only other wiring is three pins on the back for ground, 12V positive, and internal gauge light.

The thermocouple it uses is an ISA Type K Chromel/Alumel, Ungrounded, Armored, Temp Range minus 65 F to 1650 F, minimum 18 gauge wire.

Since we have the data fron TST, I'm tempted to forget the pyro for the time being and get the AT installed, then afterwards get a pyro/gauge setup installed to see what reduction we have from the TST data. For one, I was planning on making the drive down to my friends in Texas over our Christmas break (Dec 23 - Jan 2), and would like to have the beast prepped and ready to roll by then. Second, since Bully Dog is coming out with a CRD-specific version of their Outlook Monitor in February that can do the job of 4 gauges and will have detailed installation instructions, it wouldn't make much sense to go to the expense and trouble of installing one or two separate gauges now, and then turn around a few months later and rip then out and spend another $400 on this monitor.

I do have an alternate plan for at least seeing how much of a reduction the AT muffler gives. There's a Northern Tool close by, and they carry remote reading infared thermometers of sufficient range for about $80. If I can get one of these, I'm right by I-77 and there's also a conveniently located rest area on our stretch of it. Do a good run up I-77 at 65 mph, say 10 miles out and back, on the return pull into the rest area and shoot the manifold and/or exhaust pipe right behind the turbo. Then, after the AT is installed, replicate the conditions and measure in the same location.

Hmm, another thought just hit me. Go ahead and get one of the pyro setups from at work, hoseclamp the probe to the exhaust pipe just aft of the turbo, use some test leads for power to the gauge, and just tystrap the bloody gauge to the grill just in front of the windshield. That would work for a temporary test setup for getting data.

Tomorrow morning after I'm done getting a physical, I'm going to run by the AT dealer to check with him. He was going to see what he could find as far as pyros and boost gauges that would work with the CRD, and I'll see what he's found. I'll run my alternate plans by him and see what he thinks.

greiswig · **Posted:** Mon Dec 12, 2005 1:09 am

retmil46 wrote:

(SNIP)

Hmm, another thought just hit me. Go ahead and get one of the pyro setups from at work, hoseclamp the probe to the exhaust pipe just aft of the turbo, use some test leads for power to the gauge, and just tystrap the bloody gauge to the grill just in front of the windshield. That would work for a temporary test setup for getting data.(SNIP)

I wish you luck in this. However, I suspect that the thermocouple will have to be in the exhaust stream to get accurate readings. I bet the temps in the exhaust stream differ a lot and change much more quickly compared to those on the outside of the pipe. You could get some before/after relative readings, and try to extrapolate reduction in stream temperature, but I'd take that with a grain of salt.

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