Where is the best place to install the EGT probe?

Where is the best place to install the EGT probe?

A general consensus would be 1 inch to 2 inches from the exhaust valve or if you don't know the location of the exhaust valve place the EGT probe 1 to 1.5 inches from the flange attaching the header or exhaust manifold to the head. Please keep in mind that not only is consistency in distance very important but centering the probe in the exhaust flow is as well. Plan this out before you start drilling holes! See other information at www.thesensorconnection.com

I have a Mercedes turbo diesel and my idea is to monitor both the exhaust temperature and the temperature of the incoming air in the intake manifold.

I have a Mercedes turbo diesel and my idea is to monitor both the exhaust temperature and the temperature of the incoming air in the intake manifold. Is there enough range on your EGT probe to measure also lower temperatures (min. about -10 Celsius)?

Yes, our EGT probes are rated to measure -17C to 1200C.

Most of our instrumentation will display temperatures from -20C to +1300C.

Do EGT probes / sensors come with a calibration sheet or chart?

Do these EGT probes come with a calibration sheet or chart?

The EGT probes do not come with a calibration sheet or chart. They are a standard Type K thermocouple device whose output follows the NIST Type K thermocouple linearization curve. Most modern day instrumentation can read a Type K thermocouple directly. In some cases, thermocouple amplifiers are required to interface between the thermocouple & the particular measuring instrument.

Tech articles:

http://archives.sensorsmag.com/articles/1297/sw1297/main.shtml#ref1

http://srdata.nist.gov/its90/main/

When installed, are your EGT probes isolated from or are they common earthed to the exhaust manifold?

All of our EGT probes output wires are isolated (ungrounded) from the probe's outer sheath so there is not conduction between the probe sheath and compression fitting. You can read more about EGT Probe installation here on the webs site

My temperature reading on the meter is going down instead of up. Can you help me?

It sounds like the sensor's wires are hooked up backwards. Type K themocouples follow standard wire colors, Please confirm that the sensor's wiring to the meter input terminals is:

Type K Polarity:

YELLOW = + (positive)

RED = - (negative)

See chart complete chart here

Advantages and benefits of an exhaust gas temperature (EGT) sensor / probes

Operation at peak EGT, particularly on long runs like in road racing or circle tracks, will give a fuel savings meaning less pitting for fuel (increased range) as well as less likelihood of spark plug fouling.

• Aids in making proper adjustment to the fuel / air mixture ratio
• Increased precision in fuel and performance management.
• Gives you the ability to tune for fuel economy
• Decrease in fuel stops.
• Detects some types of engine troubles.
• Aids peak engine performance at cruising speeds.
• Help to prevent spark plug fouling.
• Fits any internal combustion engine.

Tuning the fuel to air ratio for peak efficiency with an EGT Probe

Increasing or decreasing the fuel to air-ratio causes an effect in the exhaust gas temperature. Decrease in the EGT reading is typically produced by a richer fuel mixture. Leaner mixture, heating occurs because of excess air. So you must have a basic idea of where you are starting from regarding base cylinder exhaust gas temperatures and know your rich or lean condition of the fuel delivery system when you start to tune with the EGT Sensor.

Peaking exhaust gas temperature (EGT) with a carbureted engine is frequently a vague point because of less efficient atomization compared to electronic fuel injection to the individual cylinders. As a result, carbureted engines tend to operate smoother at +25 degree +50 degree F on the rich side of peak exhaust gas temperature (EGT).

Fuel injected engines typically provide a more precise peak exhaust gas temperature, therefore the EGT system is likewise a more precise method of performance tuning with fuel injection.

A simple definition of peak EGT is the chemically correct mixture of fuel and air, which gives 100% utilization of all the fuel and all the air.

Benefits of EGT sensors for engine tuning:

Operation at peak EGT, particularly on long runs like in road racing or circle tracks, will give a fuel savings meaning less pitting for fuel (increased range) as well as less likelihood of spark plug fouling.

Temperature variations will occur between in between individual cylinders when using a probe for every cylinder. Typical variations of about 100 degree F between each individual cylinder can be observed with fuel injection systems, and about 200 degree F with conventional carburetion. Carburetion variation is greater because the atomization of the fuel is not as effective when compared more exact amounts of fuel metered with injectors. In colder air temperatures, the mixture atomization is poorer for both fuel injected and carbureted engines. However, with the carburetor, the fuel/air ration and atomization is less effective resulting in larger temperature variations when comparing individual cylinders.

EGT systems are not complex or expensive to install

An advantage of the EGT monitoring verses monitoring the cylinder head temperature is the close to immediate response to change in temperature verses the fuel to air ratio. The peak or point of maximum temperature is the basic reference for performance management. If you have experimented with the exhaust gas temperature sensors at the engine builder’s dyno or engine manufacturers recommended maximum horsepower, you have observed during the tuning process results in the peaking of the exhaust gas temperature via the gradual leaning of fuel and air ratio adjustments.

The peak temperature in each cylinder will vary with different power settings, changes in altitude, and ambient temperature. So tuning for specific atmospheric conditions can be critical on race day. Typically a hand held digital readout like the dual channel or single channel meters The Sensor Connection offers will have the ability to read individual cylinder exhausts or cylinder banks. Multiple channel data acquisition systems will gather and display data from all exhaust port temperature readings simultaneously. The requirements for precision of the data collection of your application will determine the type of data collection system you will need. You can find EGT probes here that meet you mechanical installation requirements

What is a Thermocouple?

Thermocouples are the most common sensor used for exhaust gas temperature measuring

Thermocouples consist of a pair of dissimilar metal wires joined typically at one end, producing a net thermoelectric voltage between the open pair according to the size of the temperature difference between the ends, the relative Seebeck coefficient of the wire pair and the uniformity of the wire-pair relative to the Seebeck coefficient. Thermocouples measure a relative temperature not an absolute temperature. In other words, a thermocouple requires a reference of known temperature. Commonly commercialized thermocouples utilize and independent sensor, such as a thermister to provide the reading of the reference temperature.

The discovery of thermoelectricity is accredited to Thomas Johann Seebeck (1770-1831) Raised in Estonia, a son of a prominent merchant. In 1802 he became a medical doctor. In 1821 he discovered that a compass needle deflected when placed near a closed loop formed from two dissimilar metal conductors if the junctions were maintained at different temperatures. He also observed that the deflection of the compass needle was proportional to the temperature difference. Subsequently he described that it depended on the type of conducting materials used, and not on the temperature distributed along the conductors. The Seebeck coefficient is defined as the open circuit voltage produced between two points on a conductor, where a uniform temperature difference of 1K ohms exists between those points... Want to know more? Go to the web page

How to Install an EGT Probe in your manifold

Exhaust Gas Temperature (EGT) Probe placement in the exhaust path requires special attention. If it is closer than 1½ inches to the cylinder head, probe life will be limited, too far away the probe will be less responsive. Should there be doubt concerning in which exhaust tube or specific placement of the probe, you should check with the engine manufacturer or your engine builder.

There are two basic ways EGT probes are installed in multiple cylinder engines either for monitoring a bank cylinders or each individual cylinder. Monitoring a bank of cylinders give you information on the over all exhaust gas temperature generated by the cylinder bank. For example when installed in a "V8" cylinder engine two EGT probes can be used by placing them in the exhaust header collector just past the point where tubes from one side become common. The probes are connected to high temperature thermocouple wire and a connector and then to a dual channel meter for monitoring. The consideration to this installation is the distance from the combustion chamber, making the EGT reading lower and giving an average of the four cylinders in each bank. This keeps the ability to gather the necessary temperature information simple.

If you require more exact temperature readings you may consider installation of probes near combustion chambers. This maybe be requirement in situations where you have the ability to tune fuel supply or air for each cylinder. This is more complicated and requires proper installation and placement of the probes. The constancy in probe distance from combustion chamber is very important in order to get reliable readings. If you require more exact temperature readings you may consider installation of probes near combustion chambers. This maybe be requirement in situations where you have the ability to tune fuel supply or air for each cylinder. This is more complicated and requires proper installation and placement of the probes. The constancy in probe distance from combustion chamber is very important in order to get reliable readings.