NTK L2H2 New Linearisation

[Slowie]

I finally had a chance to compare my LZA09 (S6 using the syvecs supplied LZA09 calibration) with a LSU4.2 (VEMS controller) as well as the motorsport grade NTK sensor running off an F88 (as supplied by Life Racing). From lambda 0.70 to 1.15 all three sensors read identically, going in 0.05 increments. Only at lambda 1.2 did the LSU4.2 show 1.29, whereas my Syvecs and the LR F88 both agreed on 1.2

Your mileage may vary.

[RICE RACING]

Pressure compensation, live action.
Done live via ECU/Dash or post process in analysis.

Javed Don.jpg (1007.43 KiB) Viewed 42529 times

lambda corrected 2.jpg (206.98 KiB) Viewed 42529 times

[ders]

Likely a 'noob' question but, is a bespoke calibration something that can be derived from the value of the calibration resistor in the supplied LZA09-E1 sensor?

[RICE RACING]

Likely a 'noob' question but, is a bespoke calibration something that can be derived from the value of the calibration resistor in the supplied LZA09-E1 sensor?

I guess it could be inferred but when I run them up they are only really 'tight' within a narrow range, so if you run rich or lean they all seem to be out a bit, some people are lucky though no doubt but as Syvecs recommend they all should be validated if you want to be certain of the reading

[ders]

Super, thanks for the input.

I'll ask Syvecs closer to the time when it goes in for mapping, to see how I can get it checked out

[RICE RACING]

FYI to others wanting to do this (on bench). The latest firmware now allows you to keep the heater on (permanently) so no more need to keep powering up the ECU to drive the heater at 20V (max 30 seconds), also you can adjust the heater in run to a voltage to equal heater element intensity on your reference/calibration NTK meter as well.

[RICE RACING]

Here is a bit more detail on how to calibrate most NTK's for use in your Syvecs ECU

[RICE RACING]

Something most don't get is the percentage of O2 in 'air' varies based on conditions.
It is pretty easy to check you just need a formula and some basic instruments and a table.
First check your relative humidity on the location where you are calibrating your sensor, simple to do with thermocouple and some water, get dry 'bulb' and wet 'bulb' reading, the delta between these two look up your relative humidity. Then get your map sensor reading for your pressure at your location, you must have localized pressure. Calculate out the percentage of O2 at this point in time and put that into your O2 instrument. If you don't do this the rich and lean spans will be out by a percentage, just as they will be in the Syvecs when you check you sensor calibration which I will display graphically below.

It's not an earth shattering difference but it is another thing to be aware of if you are flying a plane OR racing up a mountain, let alone if you are running on different days especially if the temperature and relative humidity are high V's even a constant altitude.

accuracy on different O2.jpg (556.37 KiB) Viewed 39065 times

[RICE RACING]

So here is the technical info for those who want to do this.
The errors are more extreme as you get to upper end of lean and lower end of rich scales, so if you for example dont do this or have a reference meter that is shit then it can be over 15% wrong! on a Diesel for example or on an extreme boosted engine running full rich over 7% wrong.

O2 formula.jpg (71.06 KiB) Viewed 39050 times

RH wet dry bulb chart.jpg (1014.05 KiB) Viewed 39050 times

IMG_6409.JPG (228.24 KiB) Viewed 39050 times

[RICE RACING]

Here is the adjusted sensor report/cal test.
If doing these each day the cal is run the reference meter needs to be updated to account for test atmospheric conditions, if you want it to be ultra accurate.
For most performance car shops this wont matter as they only look at their sensor when it stops working ! let alone understand how it works in most cases !

Correct DON.jpg (766.39 KiB) Viewed 39050 times

20.21 percent O2 cal.jpg (24.59 KiB) Viewed 39050 times