C127 and CAN communications

[the_bluester]

Hi all, as much as I hate to make my first post on a forum a question, here goes.

I currently have a non MoTec display in my race car and it has been giving me some issues. I am considering replacing it with a new and more modern display such as the C127. Along with this would be a staged refresh of the cars electronics (Staged for budget reasons)

The car currently has a Haltech E11V2 ECU in it and I would not be planning to replace this immediately. The documentation for the various MoTec displays list that they will communicate over CAN with various other aftermarket ECU's but do not list which ones. That leads to the question. Can anyone answer definitively if the C127 or other C series MoTec display will communicate with an E11 over CAN? That would make the first stage of an update possible and get rid of my currently problematic display.

The plan over time would be a new display (Logging enabled once budget permits) new ECU as the E11 has some limitations I have been working around for years, and then a power distribution module to enable refresh and simplification of the cars wiring.

[the_bluester]

Also, I have been digging and the E11 uses the older Haltech V1 Can protocol. I have not managed to find a DBC file for it though.

[David Ferguson]

Where are you located?

I am certain a C127 could be setup to handle any CAN protocol, but we would need info - not necessary a .DBC file, just details on the IDs and message contents.

[David Ferguson]

I found this document (thank you Google) which contains all the info you would need:

[the_bluester]

Actually in my digging I found another one which relates to the V1 protocol that my E11 supposedly uses uses. It is much more limited in the information it transmits. I am going to have to power up my old dash and look at what information it is actually pulling form the E11 as I am thought that I was currently logging information not included in the V1 data set.

Guess I had better start saving.

[Stephen Dean]

Hi,

The Haltech V1.1 protocol already has templates in the Dash Manager software, with the V2.0 ones being developed at the moment.

[the_bluester]

One other question, is a dash such as the C127 capable of unit conversions and how is that done? I have downloaded a copy of the dash manager software but it is limited in what can be done without a dash to connect to.

One of the problems I currently have is a preference for mixed units. Metric for speeds and temperatures, imperial for pressures. Particularly boost and fuel pressure. I have on my previous dash had fuel pressure and boost pressure displayed one above the other on one data page to enable a quick fuel pressure check while on track, and in PSI the numbers are smaller easier to do the maths on to confirm that is it around 40SPI "real" fuel pressure. The current dash (Racepak IQ3) can do some conversions but the manifold pressure in millibar I think overflows a register somewhere as when the appropriate conversion is plugged in, results are wildly wrong.

Firstly, can I input a formula in the dash or make a simple selection to display an input in millibar as PSI?

Secondly and related, does anyone know of a fuel suitable differential pressure transducer that I can connect to the fuel rail on one side and a manifold reference on the other to directly measure the pressure across the injectors? That would save messing around with calculations to arrive at the real pressure, either in dash or in the head. If I can source a transducer to do that then the mixed unit issue disappears as I would have a direct fuel pressure reading to display and would just make myself use KPA for boost pressure.

[the_bluester]

Hi,

The Haltech V1.1 protocol already has templates in the Dash Manager software, with the V2.0 ones being developed at the moment.

Hi Stephen, thanks for the info, is that the template labelled "Haltech ECU receive message block"? That seems to cover all of the messages in the V1 protocol.

[Stephen Dean]

Yes, that is the Haltech ECU Receive message block template.

With the units displayed, when you setup the display pages in the dash, you can choose the units that are being used for the display. This is done through a drop down list that is available when you are selecting the displayed channel.

With the fuel differential pressure calculation, as you have a C12x series dash, then there is not any user maths available to do these calculations for you, so you either have to do the calculations on the fly, or find a differential pressure sensor that will allows for this.

[the_bluester]

Actually, I have just found one, Motorcraft CM5229, combined differential fuel pressure and temperature. Exactly what I am looking for regardless of if I use my current dash or a replacement. All I would need to do is machine a suitable housing to fit it and track down the output specs.