After installing a new Autometer EGT gauge in my LLY truck and posting the results I need to test its accuracy. I have called Autometer and they are more than willing for me to uninstall and return, but that seems like a lot of work. I am looking for volunteers for a simple test. I am going to remove the probe from the exhaust manifold and heat it with a bic lighter. I know this may not be very scientific, but anyone willing should be able to achieve reproducable results. If any one has another idea, please post it.

what temp does your truck idle at in gear after the truck is warmed up and its idled for a minute or so so the egt's have had a chance to come down and somewhat stabalize? No air conditioning and also whats the air temp. what exhaust and intake mods if any? At a steady 65mph cruise?

If other LLY guys will chime in with answeres to the same q you can compare. That would be the easiest way IMO

I have done the "bic" test. Just over 600 degrees. Seams ok to me?? ratover, my LLY is "kitty-less", "muffler-less", Predator, 3 1/2" exhaust with a K&N, and a swiss cheese air box. No other mods, and so far no codes. It has been reflashed. After a short drive and parked at idle it will drop to just over 150 degrees. From a dead stop with the Predator on kill to the top of 4th full throttle, my EGT is only 900 degrees.

I dont know much about the LLY's but that seems kinda low to me???

WAY WAY WAY off...




I have done the "bic" test. Just over 600 degrees. Seams ok to me?? ratover, my LLY is "kitty-less", "muffler-less", Predator, 3 1/2" exhaust with a K&N, and a swiss cheese air box. No other mods, and so far no codes. It has been reflashed. After a short drive and parked at idle it will drop to just over 150 degrees. From a dead stop with the Predator on kill to the top of 4th full throttle, my EGT is only 900 degrees.

Where do you have the probe installed? (maybe I missed it, but this will make a difference as to whether 900 deg is reasonable or not):

1) exhaust manifold before turbo

2) after turbo in down pipe or exhaust


Need to make sure everyone is on the same page.

I used to hit the 1350 limit on the Attitude with the Juice set to zero (before I had the predator) on WOT.

I have used an oven to test gauges, against a CALIBRATED Thermistor and digital thermometer.

At best they are more than 50F off... worst i have seen is 150F
BUUT... it is the time delta that is the most telling difference. Time between high and low recovery rates of temp change.

Make sure all your contacts are very clean. Most pyros are very sensitive to resistance.

Cheff Juice Wrote
I have used an oven to test gauges
Your not using an autometer probe stuffed into a turkey's behind for cooking now are ya?

Your not using an autometer probe stuffed into a turkey's behind for cooking now are ya?

Could be worse. He could be checking the calibration by cross referencing his rectal thermometer... :eek:

Probe is in the exhaust manifold and everything is brand new. Any body got 1 on the shelf they can "bic" for me??? BarryD posted on another thread that he had not seen over 1000 on his. I am definately confused.

never said he didnt......I know I aint ever eating juice's cooking, dont know were the pyro has been:eek:

2002 stock LB7, IssaPro EGT with probe in the classical "hoot position" in passenger side manifold.

Outside air temp 60F
Engine at full operating temp
idle in neutral just shy of 300F
idle in gear 325F
WOT from dead stop unloaded to 70 mph I can hit 1100F, boost maxes out at 22psi at intake manifold (after intercooler)

Again this is a bone stock LB7, stock size tires, NO MODS
Don't think the Bic method would be very accurate as moving the probe even 1/16th of an inch inside the cone of the flame can change the temp reading considerably. The tip of the blue portion of the flame is much hotter than the tip of the orange part of the flame.

An alternative would be to boil water on your stove top. Water always at 212F at sea level (unless it is under pressure and the boiling point will rise as pressure increases)

Bring a pot of water to a rapid boil, then bring it out to your truck and immerse the EGT probe in the water........ If it reads close to 212F then your good to go, if it reads significantly lower, or higher the probe or your electrical connnections are bad. Give it a try and let us know how it works

Point of reference. I have a thin probe in passenger mainifold hooked up to a SPA guage, and a fat probe in driver manifold hooked up to Attitude monitor. Both show idle temps in the low 300 +/- range. Normal driving can be anywhere from 500 to 700 or so. Steady state, both probes track each other. Non-steady, thin probe is way, way more responsive. Thin probe has maxed SPA at 1780 something. I don't recall every seeing over 1400 on fat probe. All of the above is with HJAT only.

Simply my experience.

Could be worse. He could be checking the calibration by cross referencing his rectal thermometer... :eek:Speaking of which, why is it that a the hindquarters of a woman drop 20 degrees in bed at night? And it absolutely has to be shoved up against one's kidneys?

Ain't that the truth! ):h

GJ, Ratlover, McRat: :offtopic: :exactly: but funny as hell! ):h

RDL, if there is a high performance shop in your area maybe they can run this to ground for you. If I understand diesel's correctly they are sort of like boilers in that you can just keep putting the fuel to them and they will build more power/heat. On a light/moderate acceleration I can easily push 800-900 degrees, hard acceleration gets me into the 1100* + area. The E/J EGT probe appears very sensitive and responds instantaneously to any throttle movement. :confused: BTW, watching that dang attitude may be the end of me! :o:

If you bought the EGT gauge/probe locally maybe they can snap another one on to see if it is the gauge or the probe. Running a stock exhaust with the Predator should get you some higher EGT's when you romp on it :rolleyes:

Ol JJ kinda feels bad that I talked you into getting the EGT gauge and now it is a royal PITA. I would still recommend it! Without them we are just guessing. I had no idea how high my EGT's were. I know there have been a couple of occasions pulling the 5ver up long grades that I have pegged them! :o: Hope you get this resolved quickly! JJ :)

after driving normal, mine will cool down to 350 deg. 65 mph flat empty 600 deg. climbing 10% grade wot will hit 1400 deg. at 90 mph, with hypertech at stage 3. wating to do some testing with trailer on stage 1.

JJ, it would appear that even with the gauge I am still guessing, but don't feel bad. I knew I needed one, I just was putting it off waiting for my new truck. I was hoping somebody would do the "bic" test for me. I thought the boiling water might be a little to low of a tempeture for a good accurate test. If I don't get any feedback soon I will send it to Autometer and let them test it. I have even thought I would buy a second probe to test, if I found someone that had a spare.

How about going to a hardware, Home Depot/Lowes, grocery (sp) store and picking up a cheap meat type thermometer that has a small shaft on it, undo your pyro probe and slide it into the manifold at idle and see what it is running. Then maybe have someone load the motor in drive while standing on the brake and compare readings.

Just a thought.

BK Tool, I am going to try a variation on what you said. I am concerned that I need to test on a higher temperature range than that. Maybe I could hold the thermometer and the probe together and heat them both with a propane torch and compare. I am convinced that I need to test at or around 1000 degrees if possible. I will see if I can find a thermometer in that range. Still no "bic" takers??

I bought a infared thermometer deal for 50$.....leme see fi I can find the place again.....

Edit http://www.ai-supply.com/

Also it may be accurate in one range but get off in another.

Also, stop by any place that does commercial heat treating. Most will have a high temp hand held pyrometer set up. My buddie owns a heat treating company and I have borrowed his at times to check my in house heat treating ovens for proper temp.

Ok, a meat thermometer up to 400 degress was all I could find, so I did the boiling water test, with it also in the water. By the time I got to the truck the meat thermometer was reading 200 degrees and within the time it took me to drop my egt probe in and walk to the cab of the truck my gauge read the same thing. I still think I need to test it higher, but I am beginning to think it is accurate. Could I have done something wrong in the install. The control module is wired direct to the battery. The EGT probe is in the passengers side manifold and has a stop on it where it can only go in to 1 depth. All connection and parts are clean and new.

I have used an oven to test gauges, against a CALIBRATED Thermistor and digital thermometer.

At best they are more than 50F off... worst i have seen is 150F
BUUT... it is the time delta that is the most telling difference. Time between high and low recovery rates of temp change.
GJ, re your statement about time between high and low recovery rates. My E/J EGT's on the attitude are remarkably fast, going up and down. Is this what you are referring to, I take it this is a good thing! JJ :)

Just talked to Autometer again. Explained everything to him. He says from what I have said and tested, my temps are accurate. Could the reflash I got on my truck lowered the EGT. My fuel filter is fairly new, but is it possible that it could be getting plugged up and dropping the EGT. If thats the case maybe I can tell when I need to change the fuel filter just by looking at the EGT. My gauge moves up and down like my tachometer, and almost in sink with it. Is that good?

I bought a infared thermometer deal for 50$.....leme see fi I can find the place again.....

Edit http://www.ai-supply.com/

Also it may be accurate in one range but get off in another.
I hope you were happy with it. I just ordered one. You should get a commission!

GJ, re your statement about time between high and low recovery rates. My E/J EGT's on the attitude are remarkably fast, going up and down. Is this what you are referring to, I take it this is a good thing! JJ :)Kennedy has 'fast reacting' EGT probes for sale.
They are more for the racer than anything else. That said, I am a gauge Freak.
3 Boost Gauges (including the attitude) Drive press, Top Turbo
2 Pyrometers (soon to be 3) Pre turbo hoot method pass side, preturbo drivers side, Post turbo 4" from band clamp

*Sigh* at least WESTACH makes a dual and triple pyro in a 1 gauge chassis.
The only gauges i am missing now is Fuel Press (no lift pump yet though)
Turbo Tachometers (still looking for an inexpen$ive solution).

Ah well..... you only live for the last day you savour!
Life is to be lived 1/4 mile at a time... everything else, before and after is just waiting or coasting along.

"He says from what I have said and tested, my temps are accurate. "

But of course! ):h You don't think he just wanted to get off the phone now do you? :o: The one factor that makes your situation stand out from the others is you have removed the CAT and exhaust and running straightpipe exhaust. Question is just how much of a difference does it make?

Your EGT's are well below what others are posting, especially on hard runs up to high speeds. You tow as well which will jack the EGT's up considerably. When you get that new "gizmo" you just ordered we'll have our answer. How long til you will have it?

Got Juice, do you find the attitude consistent in regard to EGT's as the other gauges? It seems to move immediately up or down. JJ :)

I have played with mine a bit and like it, dad bought one to replace his raytech that grew little legs. Listed features it compares well to a very expensive rayatech gun. They have been on "special" for about 6 months now???

It may be a PITA to test your probe........the lil lazer isnt exactly were it takes its reading from.

Got Juice, do you find the attitude consistent in regard to EGT's as the other gauges? It seems to move immediately up or down. JJ :)
The Attitude's temperatures are consistant with my other Pyrometer's
The strength of the *** is that it will display the maximum (and minimum) values before the analog gauges catch up. For accuracy in that regard i give it a 9/10

And this might be nit picking, but IMHO the attitude would be better if its display of the EGT might be at a lower resolution IE 10 degree increments rather than what it is currently set at. I find it to be a minor annoyance that the EGT display 'jumps like a bean' when getting warm.

That said, the accuracy of the gauge seems to rely (for the most part) on good solid connections of the lead wires from the probe to the gauge, and a good probe to begin with. Measuring the electrical resistances is one way to 'match' probes when they are exposed to a given temperature. In fact it is not necessary (unless calibrating to gauge) to know what temperature the probes are when you electrically 'match' them..... so long as they are both at the same relative temperature to each other when testing the current output.
( Yes, the element on a stove works nicely for this... make sure the wife is not home ) I have found that a 3-5% electrical @ load variance (at each element setting ) to be about the best i have been able to achieve.

FWIW anyway.:o:

And before anyone says i have waaay to much time on my hands.

I'm single.

N'uff said:muahaha:

Something tells me RDL is firing up the stove as we speak, err post! :p:

I am thinking about removing the muffler on my truck, today if possible, to see what affect that has on EGT's. JJ :)

JJ, what about the cat?? Do them 1 at a time and let us know the results??

RDL,

There was quite a discussion a couple of months ago about removing the CAT. IIRC the concensus was it didn't reduce EGT's significantly and was throwing codes. The muffler sounds like it has a lot of turns in it which likely causes quite a bit of EG restriction. :rolleyes:

Since the CAT is a federal thing and the muffler a local thing I figured the muffler can go. Speaking of which I need to make some calls to a few muffler shops. JJ :)

JJ, if you want to pay my expenses, I would drive down and bring my welder and some pipe???:ro) Been wanting to do some diving this winter anyway. Well the local muffler shop may be cheaper.

As far as the cat goes, it seemed to help me the most, sound wise, and I am banking that since this is the first year for them on a diesel, most people would not even know they are susposed to have them. I still may put it back on. I have not seen any concrete evidence that it has helped performance or mileage being off, except my questionably low EGT.

OK, half my expenses??):h

JJ, if you want to pay my expenses, I would drive down and bring my welder and some pipe???
Sure! ):h :badidea: :funnypost :exactly: :muahaha: ):h :D :wtf1: :banghead: :wtf: :devilfing :duh: :drinking: :crazy: :confuzeld :bounce: :smashfrea :thumb:

We have totally too much time on our hands!

Yep! I was on the phone with a muffler shop. $90 to straightpipe it, though they don't recommend it since the pipes don't line up directly. He recommended going with a Pro Flow 4" muffler for $240. Surprised? :o:


He stated you don't ever want to straightpipe a turbo-diesel. The more I think about it I likely used the wrong terminology. Duh! JJ :)

I've seen people use a straight peice of exhaust and you end up with non bent radi but it still works......I think people that when this wroute used 4" maybe, filled in the slight gaps with weld. janky but it works. It can be done with nice mandrel bends if you buy a 3.5" mandrel U and a small amount of 3.5" staight pipe and then you slice the U in hafe in the middle of the 180 bend and turn that and weld it so you end up with an S and weld that dude in place. Well its not exactly an S.....but one 180 mandrel U should get it taken care of......or if they bend a peice(it wont be mandrel but oh well.....)

People call "strait piped" many different things. IMO its just pipe, no muffler and no cat. So just mean its a muff less system. Some call pipes out the back with muffs and cats straight piped since I guess the pipes exit striahgt or something???

Or just go get you some flex pipe and a sawsall and some clamps and :grd: LOL (dont do that BTW:badidea: and janky as Censored )

Ok, where's Kennedy on this thread?? The guys got both LB7 and LLY's and he has tried every different combination on the dyno that you could think of and SELLS the stuff himself? He should be able to tell us what is going on??

:help:

NOTE: My temps as stated earlier are with the LB7 which did not have a cat from the factory and I have now replaced the whole thing with a 4" MBRP.

I built mine out of the bends from an old exhaust system. I cut the muffler off and used it for a pattern. It took me less than an hour and there are nothing but nice flowing bends.

Nice work!

BIC/butane flame should be 1300 or so if the whole probe junction is in the flame. Butane soldering irons get up to about 1400 degs, according to the label. I will test mine the next time I have the fender liner out.

It's even easier than that, just get two 3.5" 45* bends. Fits perfectly

Damn man, that is very nice work

RDL, what was the final verdict? JJ :)

AutoMeter is susposed to send me a new gauge. Still waiting.

I can only get my Attitude to idle down in the 260-265 degree range.

OK, here's the update. Replacement gauge in. Also had dealer replace fuel pump.

No chip, stock filter (modified box), no cat, no muffler, 28,500 pounds gvw heading up hill towards Denver as I type, bucking wind, 13 feet tall, 5.6 mpg.

300-375 degrees at ildle, Max egt 1250 degrees!

Now that's more like it on those EGT's! :ro) While we really appreciate the info, put the freakin' computer down and drive safely you idiot! ):h 28500lbs towing uphill with a load and posting on the DP? :o: Now that's an addiction Rick!

Drive safely, we'll talk after you get off the road! JJ :) Geesh!!!!!! Where are my heart pills Mama JJ? :eek:

Actually, JJ, I was sitting in a rest area when I typed that, but i'm driving now. Just kidding. I'm fueling now. Typing while I drive makes me type funny! ftftvugdfrrdfr
fcdtyuyifd4dd!

I also tried my K&N element for the last 50 miles. No EGT change whatsoever. Another myth busted!! Well gotta go rexexxesersaqz12cvbnuiljl.

RDL, why aren't you running the Predator on this run? Sounds like your EGT's are right in line with where they should be, especially towing that heavy up hill into a headwind. Be safe out there! JJ :)

Looking for a baseline on the EGT. Predator test will be next.

I did the "Bic Test" with my Di Pricol, and the hottest I could get it was 800°F. The readings were consistent and I think the probe is completely fine (brand new).

So, I'm not too sure how accurate this "test" is.