Cheap pyrometer

I actually purchased one of these IIL pyrometers, and will be installing it soon with an ATS turbo on my 86. First impressions, quality seems to be good. Fits a standard gauge pod, comes with 1/8 NPT stainless hardware, vs 1/4 NPT. No biggy. I plan to do some quick baselines to see how accurate (or inaccurate) it is out of the box. The reality is, so much stuff we purchase is made overseas, it is difficult to know what is good, or not so good. I purchased two VDO gauges for the same install, both aren't made in Germany! How times change.....

https://www.ebay.com/itm/DIGITAL-EG...6:g:BFQAAOSwjk9ZU9al:rk:2:pf:1&frcectupt=true

I like this one over the analog and the plus side I have it programed to shut off my propane injection off at a set temp.

I bought this high dollar piece of equipment off of Aliexpress. I had to tear it apart on my desk and through a series of button clicks i got it changed over to Fahrenheit. On the desk the temps seem to be accurate, hopefully i'll get it installed in the truck on the driver side sometime in the next year. I have a auber instruments one on my truck (installed probably 8 or 9 years ago) on the passenger side so i'll be curious to see how similar the temps between them are.

Looks like I got my money's worth (or not). The probe appears to be defective. It does have continuity, about 13 ohms which is in the ballpark, and the end is not touching the wall of the wye (first two things I checked)!

But the output signal is a very slowly drifting-upwards level of 1.5 to 1.8 millivolts, even with the engine warm and revving, way too low according to K-type thermocouple charts with a 200-300F hot junction. The gauge scale starts at 300 anyway. I drove up and down the road and got into boost, but the needle still didn't budge off the low pin (300).

I also hooked up the leads to the Triplett panel meter and it also gives roughly a 150F reading. Reversing the leads makes the meter read downscale instead of upscale, so there is some kind of thermocouple junction out there. But I'm betting it's shorted in the cable or at the probe body, instead of the two wires meeting at the probe tip like they're supposed to.

Tomorrow I'll apply a few millivolts DC directly to the gauge and see if it responds. My bet is that it probably works since it sweeps the entire scale and back at power-on, but at this point I'm not sure of anything yet

BTW the Autometer 2654 that Amazon had for $130 is now $177

Have you got anything else that reads type K? My DMM will read thermocouples. That’s where I’d start or hook another probe to it. Cheap wire thermocouples can be had for a couple bucks. Hold a lighter or heat gun to it and see if the gauge reads.

DrCharles said:

BTW the Autometer 2654 that Amazon had for $130 is now $177

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I bet it works when you take it out of the box though lol

I totally understand if you just don't like the digital gauges and I had my heart set on going all mechanical with Isspro, but the digital setup offered through Auber Instruments or TheSensorConnection is pretty darn nice and cheap. The reaction time to changing temps is very fast, gauge fits nicely in empty spot next to WTS light or in place of ashtray, and with it being digital you can wire your own idiot light/buzzer. Plus with digital I find it easier to see at a glance if I'm at 1100 or 1150. I do frequently run right near the limit for EGTs and find the accuracy helpful.

Today I put the pyro gauge on the bench and checked out the scale reading vs. DC millivolts applied, at major scale divisions (100F). It is quite close with the K-type thermocouple table adjusted for in-cab or room temperature (the cold junction is usually 32F in most tables).

So the problem is the probe or wires, as I suspected. Will order another and I'll check this one before snaking the wire under the dash, and getting under the truck to secure it with the compression fitting!

I saw a review of a really cheap Chinese probe (less than $10) on Amazon where they said 1 in 3 are defective out of the box. Maybe I should invest in the $70 probe from Autometer...

MtnHaul said:

I totally understand if you just don't like the digital gauges and I had my heart set on going all mechanical with Isspro, but the digital setup offered through Auber Instruments or TheSensorConnection is pretty darn nice and cheap. The reaction time to changing temps is very fast, gauge fits nicely in empty spot next to WTS light or in place of ashtray, and with it being digital you can wire your own idiot light/buzzer. Plus with digital I find it easier to see at a glance if I'm at 1100 or 1150. I do frequently run right near the limit for EGTs and find the accuracy helpful.

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yup, good price and good quality, it was recommended to me when I asked last year and it wasn't exactly what i had in mind either, but beggars cant be choosers
only a year old for me, but no issues at all, the display is bright and easy to see in the day time, easy to read at a glance

you can buy just a probe from auber

nothing more expensive than buying the cheapest stuff

Follow-up: I replaced the probe with an $18 generic one. The gauge, as I expected, works properly and gives the expected readings while driving.

However, the original probe also now works when connected to the Triplett panel meter! Go figure.
There must be an intermittent short somewhere in the cable. It's the only way that it could have kept continuity at the gauge end of the wire, but still not give a reading on either instrument.

I bought another cheap pyrometer which hardly cost any more than a spare probe. Haven't experimented with it yet since my not-quite-as-cheap pyro is working fine.

Meanwhile, here is a pic of the box for your viewing pleasure:



It's not only hi-performance and high quality, but it's fast and furious!

MtnHaul said:

I totally understand if you just don't like the digital gauges and I had my heart set on going all mechanical with Isspro, but the digital setup offered through Auber Instruments or TheSensorConnection is pretty darn nice and cheap. The reaction time to changing temps is very fast, gauge fits nicely in empty spot next to WTS light or in place of ashtray, and with it being digital you can wire your own idiot light/buzzer. Plus with digital I find it easier to see at a glance if I'm at 1100 or 1150. I do frequently run right near the limit for EGTs and find the accuracy helpful.

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+1
Check my turbo tale thread for more on my install. I totally get analog for the visual. My honest opinion is the digital is better for accuracy and chicks dig it.

And I am a guy who programs analog displays into equipment that requires direct user control or feedback. 30 year old truck needs a little bling anyway.

I've been reading analog (and digital) meters for well over 40 years and I can tell 1100 from 1150 at a glance too

You're probably also aware of the difference between accuracy and resolution. Knowing that the temp is "about 1100" is close enough for our purposes. The digital may say it's 1099.8365 but if it's not accurate and the actual temp is 1203.5678, all those digits of resolution don't help

Accuracy vs precision... I follow the GUM for expressing measurement uncertainty. I just like the fit of the Auber. And chicks dig it!
Kidding aside, I really liked the clean install of the digital and the alarm function. I don't chase insignificant figures...