EGT sensors
Turbo Mini Forums

Does anyone know of a US or UK source of ex gas temp sensors? This is one feature I intend to add to the MS project as the V3 board can support this and I want to make sure every option is used in the development of the new MS system and I am ordering the boards tonight or tomorrow.

Peter

Editor

MAGA7INE
Seven Magazine
The brand new quality Classic Mini Tech and Journal
Issue 1 out late 2027.

Peter,

You can have a look at:
http://www.aircraftspruce.com/menus/in/pro...enders_egt.html

MS-II supports logging on EGT but even the V3 board requires an additional circuit to be able to connect the EGT probe (K-type thermocouple) such as:
http://www.megasquirt.info/gpio/egt.htm

The circuit could be done on the proto section of the board.

Jean

http://www.jbperf.com/

if you find out can you let me know please :) interested in it but its soemhting i have never heard anyone over here useing to tune a car, outside a rolling road atleast.

cheers,
denis

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Thanks Jean, I was going to email you direct about the version you would like to have. 2 has the options of knock sensors, 2 O2 sensors and the megasquirt and spark extra code and add on board also allowed for water injection with pulse width modulation and a seperate water injection table. I would like to do these if possible, especially the water injection as we can then adapt this to drive methanol fuel enrichment.

I am going to be running methanol as well, (I am aware of the severe limitations with regard to duty cycle and injector capacity, but I have a possible solution for this), so EGT logging and wideband lambda would be nice :)

Knock sensing would be a very nice addition. What do you think is reasonable/possible?

Peter

Editor

MAGA7INE
Seven Magazine
The brand new quality Classic Mini Tech and Journal
Issue 1 out late 2027.

Peter,

The megasquirt and spark extra code runs only on the MS-I cpu. It is also done in assembler. The MS-II cpu is programmed in C and has much more memory and better precision.

The MSnS-e code has more features but the potential for expansion is limited. The MS-II has fewer features at the moment and fewer auxiliary inputs/outputs but it has a CAN interface which will allow it to connect to expansion boards which will allow a LOT of additional features.

Also, since I don't know the HC08 assembler and the fact that the MSnS-e code already usese almost all the memory, I did the code in C for the MS-II. That means that at the moment the code would be limited to 2 O2 sensors and either knock or EGT sensor. You won't be able to have all of them together. But when the upcoming GPIO board is out these limitations will go away. By the way, knock sensing and knock retard is already in the MS-II code.

The water injection can be done in a few different ways but there is nothing in the MS-II code at the moment for that. The best method to use would depend on your setup and which compromise would be best. If you run a single injector per port then the easiest method would be to use the dual table mode and put the water injection on the second injector driver. If that's not good and you don't have an idle valve or stepper motor, then the idle valve control could be used but that would require code changes. Another way would be to use a spare port and open the water injector solenoid with the same duty cylcle as one of the injector driver. That would also require some code modification and correct sizing of the water injection setup. We can discuss that further if you want.

Does it clarify things a bit or does it make it more confusing? Let me know if you need more information.

Regards,
Jean

http://www.jbperf.com/

Email sent Jean, thanks.

So it's MS2, V2.2 board.

Dual table mode sounds like the best solution then, with the manifold plumbed for and extra pair of injectors for the methanol enrichment or for pure methanol, I would just have to swap in another fuel rail and injectors, (which need to be different anyway), at the track and upload another map for it.

The knock sensor should I think be used, far more important at the moment than EGT which I could monitor anyway with a gauge and have my other half log them with a pad of paper, LOL, she did it for my first lambda sensor install bless her!

Lambda works with Methanol just fine as well I have found out as it just measures O2 and it doesn't matter that stoich is 6.5:1 as the sensor just outputs voltage based on exhaust oxygen content, which is neat!

Just in case anyone is wondering, I'm not going to be using water injection, I was just going to use the water injection table to inject methanol to improve octane and reduce cylinder temps.

That clarifies things very well, thanks! I would like to know more about the GPIO board though.

Peter

Peter

Editor

MAGA7INE
Seven Magazine
The brand new quality Classic Mini Tech and Journal
Issue 1 out late 2027.

Actually, it should be MS2 with V3 board since there will be a need to have a toothed wheel with more than likely a VR sensor. The V3 has a built-in VR conditioner which would need to be added to the V2.2 board. Another addition that would be needed on the V2.2 and that is included on V3 is the active flyback which is needed for low-impedance injectors. Since you're likely to be using those since most larger injector are low impedance, the V3 board again makes more sense.

If a Hall sensor is used for the toothed wheel and high impedance injectors are used then the V2.2 would be ok. But if you're planning on adding some options, the V3 board with its proto area is more practical than having to use a seperate board.

One thing to be carefull about with an O2 sensor and different fuel is that while it's true that stoich will always be at lambda = 1.0 and reported as such, there may be some calibration needed for richer and leaner lambdas. You may not be able to rely on what the sensor tells you about how rich or how lean you are even with a wideband sensor.

The GPIO board is an add-on board that is controlled by MS2 through the CAN interface. It contains another CPU and other circuits for inputs and outputs. You can have more details at:
http://www.megasquirt.info/gpio/

Regards,
Jean

http://www.jbperf.com/

In answer to the original question, I use these:

http://www.omega.com/pptst/TC-NPT.html

I make steel bungs, tapped 1/4 NPT, which I weld to the exhaust manifold not far from the port. On the dyno I use the high speed data acquisition system and on the road I use the slower USB acquisition with the laptop for a display. When I'm done messing around I just plug the holes with a pipe plug.

www.starchak.ca and www.TDCperformance.ca