EGT probes

[RICE RACING]

So due to popular demand I decided to show the set up testing the Don Mega Probe as an effective alternative to a fast acting ACT sensor, the set up and actual test is in the below video, where you can see the placement and various sampling tools.

The ACT was calibrated via the reference meter in ice bath warmed to boiling to generate a full curve calibration, and run this way. The OMEGA thermocouple meter was fitted with an ultra fine type K wire (0.3mm diameter!) and another fine wire was fed into the Syvecs along with the Don Mega Probe, finally the new ACT sensor was allocated to act1.

You can see that in normal measurement times and ranges the 'EGT probe' is faster and more accurate than the act sensor, this test was repeated many times with different locations tried for the act, the only way it could better the EGT probe was when jammed up into the runner as an effective dead head to the flow or air causing it to back up into it rather than pass through it, anyway hope this shows how versatile these are. Totally different topic is how in accurate all of them are V's a fine wire type K which makes you wonder how accurate some manufactures 'fuel model' based ECU's are when relying on this input to 'guess' air density

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[RICE RACING]

Here is close up shot of sensors:

• Fast Acting ACT

• Type K Fine wire 0.3mm diameter wire

• Type K Fine wire 0.5mm diameter wire

• Type K Don Mega EGT Probe

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[RICE RACING]

Below is the test conducted in boiling water (fast acting ACT still using default calibration linearization) so ultimate reading was incorrect! but the response is what is important to understand. The later log Syvecs implemented the ability to calibrate the onboard EGT inputs, so these were set up with the Omega simulator in the latest log as well. Any offset to temperatures are a function of the various probe characteristics rather than instrumentation deficiency.

Sampled after ~1.5 seconds exposed to majority temp input.
Obviously in an engine the thing is used to read air (and fuel) mixtures, and the mass flows are much higher than simple heat gun test on bench, however you can see that there is a large transient delay and offset to real temperatures (once calibrated correctly).

Anyway somewhere between these two extremes is what to expect in reality, either way a don mega probe can be used to sample gases is the main point, and it wont melt either + be allot more durable too.

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[stevieturbo]

purple is your probe, black is what ?

[RICE RACING]

purple is your probe, black is what ?

*as per comments in left log file*
purple = 0.5mm diameter wire K type
black = 2.0mm tip diameter Donmega probe

[RICE RACING]

Here is what 1160 deg C pre turbo EGT does to a Garrett turbine wheel
All 6 donmega Type K thermocouple probes are still working as new, despite small bend from the abuse

Great way to test durability though

molested EGT 1160+deg C.jpg

This above long term test is still going on the same set of donmega probes.
Tried 3 different turbos:

• Small

• Very large

• Large

The EGT consistently has shown over 1100 deg C, latest set up 1143 deg C.
After a collapsed catalyst, and flex section, different turbo's, locations for TIP sensor (thought this was issue, stupidly high TIP) it was decided to actually test the TEP, and guess what? its very high, so whole new post turbo exhaust is being made.
As comparison same engine type with similar turbo set up is ~200deg C lower at same operating points (excess fuel, type, ign etc) with same sensors.

These probes are a very useful tool

[RICE RACING]

Another nice instal of the donmega probes
donmega VR6.JPG

Here is a bit of information showing temperatures on the above engine

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[RICE RACING]

More donmega probes, real TIT readings

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[RICE RACING]

This may be of use to some people, this is the specification for height setting range on the donmega probe/s.
Bosses pictured I had to make cause ones bought off internet are shit so customer molested the holders threads and all were different heights, threads loose etc make sure a proper machinist does these for you please. Drilled, taper reamed, then hand taped! to correct fit so the adaptor just is near bottoming is the correct *only* way it gives a full lock on the thread and is leak/stress free. Picture of proper anti seize is included for reference as well.

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[RICE RACING]

As above cont...

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