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Digital Pyrometer & Boost Gauges - VEI Systems

February 22, 2014, 03:31:15 pm

Most pyrometer and boost gauges have installation and calibration issues. 

Mechanical boost gauges require a long tube run from engine to dash to carry the boost psi. 

Pyrometers require long runs of special wires to a gauge that is measuring millivolts.
The length of the wire contributes to voltage loss and the meter's controller must be calibrated with the probe in a known cold and hot temperature.
Long wire lengths and higher temps often are not as accurate as lower temperature readings.

We recently found and installed VEI digital pyrometer and boost gauges, which display current readings and maximum readings. 
Gauges are easily programmed for display brightness, number resolution and other settings.
Display is numeric and bar-graph at the same time.
VEI Systems

The pyrometer has a unique design where the pyrometer probe and controller are attached with a non-removable 3' metal shielded cable.  Controller is factory calibrated, greatly increasing accuracy and simplicity.
The small controller at the end of the pyrometer cable requires 12-volts and ground and a single ordinary signal wire from engine to dash gauge.
We chose to drill a small hole in exhaust pipe just after turbo to insert pyrometer probe, fastening it in place with a stainless hose clamp that also has a small drilled hole.

Small boost sender requires a ground and two ordinary wires run from engine to dash gauge.  A small diameter rubber hose connects sender to engine.

The gauges do not seem to be widely sold, and we found our VEI gauges at egaugesplus - Egaugesplus home page, which seems like quite a good place to business with. 
Boost gauge label:  V1-BHEP-MR/B v5.20.
Boost sender:  SEEN-P70B
Pyrometer gauge label:  V1-PYF-MR/B v300.11 
Pyrometer sender:  SEN-TCI

Boost psi readings will verify engine performance.  Pyrometer readings will let us know when we are pushing engine too hard, like when climbing a mountain, as too high temps can damage and overheat engine.  We drive up hills with an eye on tachometer & pyrometer, which may result in a down shift to keep us running cool and safe.  No more high coolant gauge climbing temperatures.

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #1 – February 22, 2014, 06:34:00 pm

Unless fuel has been added to the injection pump, the factory settings (or Gale Banks settings) should keep the EGT below any number that would damage the engine. Automatic transmissions really make driving almost idiot proof (almost). EGT gauges are very useful for detecting a turbo seal that is leaking oil into the intake. This has the potential to raise combustion temps in a hurry and burn a hole in pistons. Some of the newer EGT setups allow you to set the maximum temperature above which it will trigger an warning on the display. Nice to have a probe for each cylinder.

I almost bought a Mack (Brazil VW) truck with an 8.3 that had a turbo seal failure. Nice neat holes in a couple of pistons but no cylinder wall damage that wouldn't clean up.

Detroit 2 cycle owners don't have to worry as much as the nature of the beast keeps the EGT down a couple hundred degrees over the 4 cycles.

Pierce

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #2 – February 23, 2014, 10:25:52 am

Great subject, Thanks Barry & Pierce--

We have a 96 U295 36' Turtle with the 300 Cummins and tow a 02 Mini Toad.  The Turtle came with optional Banks gauges.    After 15k miles around the country, am starting to get familiar with the relationship of variations between the Banks gauges and the factory Water and Trans Temp gauges.  Am very conservative with climbing grades and try not to run above top middle of the gauges, which is obviously light pressures and temps.  Occasionally traffic warrants a little more speed, like on the LA Grapevine stretch of I5.

My question is--what is considered a Max EG Temp and Max PSI Boost for safe running.  Second question is about watching for other possible problems these gauges would indicate, like the temp and pressure leaking into other components causing damage.  What am I watching for in the gauges?    The Banks gauges are mounted below the dash and require taking eyes off the road when checking, has taken me a long time for my senior eyes to get accustomed to variations in readings.    On aircraft, most  gauges have color ranges to indicate safe operating ranges, would like to make a couple of marks on the gauges for quick ref, just not sure what is medium and high for marking.

Thanks for the help

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #3 – February 23, 2014, 10:53:55 am

 I guess it depends on whether you have any mods by Banks along with the gauges. I have the "stinger" on our 8.3 350 and have a few times pulled 34lbs on a steep climb and temps around 1100 without any problems. Since removing old oem muffler the temp' has dropped some to about 1000 with boost still same. It is rarely I go to that Boost and 28 is normal I guess.
I watch the VMS very closely while climbing along with Banks gauges and they are pretty close to the same.
JohnH

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #4 – February 23, 2014, 11:12:53 am

Measuring the EGT just before the turbocharger (TI or turbine in) should see about 1200 degrees max. 1250 is considered about max with most modifiers for extended running. Some GM PUs have a 1450 max for 3 or 4 minutes. Most gauge makers recommend TI readings instead of TO (turbine out) as the TO readings may be 150 less and give a false sense of security.

With many experimental aircraft, there may be probes for each cylinder with a lcd with one after the other so you can see if one cylinder is running hotter. Not so important with a diesel as diesels can't run lean and cook. With less fuel/more air, they run cooler and produce less HP.

I know some diesel operators use the EGT for getting the best fuel mileage. Best to contact a company like Banks with your engine model and EGT probe placement for their recommendation for conservative maximum EGT temperatures and best fuel economy temps.

If the ambient is cool, I am usually petal to the metal on grades and think nothing about keeping the RPM against the rev limiter as long as the coolant temp does not go above 200. With stock boost pressures and stock fuel programming, it would be hard to exceed max EGT but Banks will be able to give you an expert opinion based on millions of miles of experience.

Pierce

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #5 – February 23, 2014, 12:03:47 pm

  That is the way they did mine with pyro TI.
JohnH

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #6 – February 23, 2014, 03:00:19 pm

Installing pyrometer probe into exhaust manifold is recommended, but I was not interested in drilling a hole into our cast iron, so I picked just after the turbo where we have a 4" steel exhaust pipe, knowing we are not getting the hottest temp. Pyro tip is 2" into pipe, and we try to keep temp reading from going much over 1,000 degrees at that location.

Knowing that our previous pyrometer could have had inaccuracies because of calibration and very low voltage long wires, we are much more confident in the number displayed with our new VEI pyrometer.  When we saw 1,100 degrees, we were not sure that our engine was not running hotter than the display.  I have no idea if any other manufacturer uses the VEI design where the controller is fixed to the pyrometer probe, eliminating all calibration and long wire problems.

Our style of driving up mountains is to keep a light throttle touch, with the objective of keeping coolant & exhaust temps in line with tachometer at about 1,800 or less, by manually shifting. Never to the floor and try to avoid transmission shift hunting. We used to drive up hills the same as on flatland, but saw coolant temps climb. We figure that the ratio of up hills to down hills and flat land is small enough that we can take our time getting to the top and sometimes we even pass a truck, but not often. Changing from a 4,200 lb Jeep Grand to 5,400 lb Jeep Grand did not help the situation. But our Aero resonator did give us back some power we lost with the heavier Jeep.

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #7 – February 23, 2014, 03:17:30 pm

We have the Banks Stinger on a Cummins C8.3-325. The pyrometer pickup is just before the turbo inlet. I'm not sure where the boost line is inserted into the intake system. I made a mount for the gauges from wood and put them above the dash near the left window pillar. Installation had been below the dash they were difficult to see.

The previous owner had noted 1400F as the absolute maximum temperature for the pyrometer reading. I put a redline on that face of the pyrometer at 1300F. We normally run with cruise control, which means full throttle on significant hills. If we (bride drives also) see the pyrometer at 1200F, we normally disengage the cruise control, select an appropriate gear, and back off the throttle a bit. The temperature drops immediately. We'll continue to pull at 1200F, but choose not to exceed that temperature.

Maximum boost is normally about 26 psi. We can tell how hard the engine is working by pyrometer and boost gauges. Water temperature never goes above 180F unless something is wrong. A hydraulic failure caused our only excursions about 180F.

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #8 – February 23, 2014, 03:36:44 pm

Rfrum, (another name?)

Turtle's Banks pyro and boost gauges can probably be moved to a better eye ball position.

My sense is whatever you see in max boost department is your baseline and if you see lower when engine is working hard, you may a leak or other problems. We used to see about 20 psi, and now after some tweaks see around 28 psi. But we have yet to take Homer out west for a real test.

EGT above 1,000 are something to keep an eye on, with 1,200 sounding like a safe top end, assuming the EGT gauge is calibrated ok, so you can count on the readout. We also use EGT gauge to know when to turn engine off, by waiting for about 300 degrees. An engine working harder produces more heat, measured in hotter coolant and exhaust. Remember the two meters only measure heat at one place, so there will be much hotter places in the engine that one needs to think about. So running as cool as possible may have its advantages.

We also use Turtle name, since someone told us RVing is like taking everything with you like a turtle.

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Re: Digital Pyrometer & Boost Gauges - VEI Systems

Reply #9 – February 23, 2014, 05:07:55 pm

THANKS FOR ALL THE GOOD RESPONSE, MUCH HELPFUL INFO.  WENT TO THE BANKS WEBSITE TO LOOK UP THE STINGER AND HAD DETAILS ABOUT GAUGES AND READINGS FOR 8.3 CUMMINS. 

HAVE ALSO BEEN USING 1200 EGT AS A TIME TO BACK OFF ON A CLIMB.    WILL RESEARCH THE AERO EXHAUST OPTION TO HELP EXHAUST FLOW FOR TEMP AND OTHER PERFORMANCE BENEFITS--ANOTHER GOOD IDEA.

PREVIOUS TOAD WAS A FULL SIZE BRONCO, CUTTING THE WEIGHT IN HALF WITH THE MINI HAS EASED THE CLIMB LOAD SUBSTANTIALLY--HARDLY KNOW IT IS THERE EVEN WITH THIS 300 HP VERSION OF THE 8.3.


THANKS--RALPH & SANDY--(RFRUM)

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