If it's not really about tuning or wiring. Then it belongs in here.
A Friend of mine has acquired a motec M150 for use in his BRZ. He is now interested in a motec dash display. If you already have the Level 3 logging licence in the M150 is there anything to be gained by purchasing a dash display that also logs? Are we losing anything thing by logging with the M150? Can most our logging be done with the M150 or will we be limited eventually? If anyone has some experiance or information it would be helpful. I am trying to compare the two logging capabilities.
You won't easily have any way to log channels attached to the dash in the M150 (yes, it is possible to transmit channels from the dash to the M150, however you will only be able to put those into channels defined in the M150, which is not nearly as flexible as the Dash). So if you were testing radiator efficiency, and wanted some extra coolant temp channels, there would not be an easy way to log "Radiator Inlet Temp" and "Radiator Outlet Temp", or a differential pressure sensor used to "Radiator Differential Air Pressure".
Dash Logging is also helpful if you have several external CAN devices. It's not easy to deal with more than a few pre-defined CAN devices in just the ECU.
However it's easy to add logging to the dash just when you need it. So you can easily defer this until the need arises. I once had an engine running problem with a car that had a MoTeC dash without logging, and we were able to enable logging within 30 minutes and capture data when the car returned to the track.
I find it handy to have both ECU logging (particularly if you are debugging paddle shift or traction control), as well as dash logging for most car setup / driver coaching needs.
There's no right or wrong way to go about your logging and what you do will depend on what information you need to look at and at what rate. I personally use the dash as my logging hub as I have multiple sensors wired to this, as well as other inputs coming into the dash via CAN that the M150 doesn't have or need.
On the other hand with level 3 logging you can log some of the key aspects of the ECU at 1000 Hz so this is where I go to set up critical aspects such as gear shift control etc.
The way that I look at logging on vehicles is that the ECU log files are purely to do with the engine, this may also include some gearbox data if the box is using Gear Change Ignition cuts or Paddle Shifts. I will include vehicle speeds and acceleration loads in the engine log set as well, as these are very useful when diagnosing issues such as oil pressure.
All other systems on the car will be logged through the Dash, with some engine data included to allow for ease of data overlay alignment.
I just thinking about the other side around. I'm going to install a C125 Dash logger and and a M150 in a month. Is it worth to upgrade the M1 logging, or can everything be logged on the dash? What is the max. transmitting rate from the ECU to the Dash? Can all engine parameters be logged on the dash?.
I have an M150 in my car, and I had a C125 as well (since upgraded to a C187 as I had run-out of capacity in the C125) so I can answer this.
There is a large number of channels transmitted across the CAN Bus from the M1 that can be read by the C125 (or any other Dash/device with suitable templates). The rate that these are transmitted varies, but the important channels such as Engine Speed, MAP, TPS are transmitted at 100hz, with the other channels being at either 50Hz (boost Pressure, Cam Aim/Position) or 10Hz (Temps, Warnings, States)
The complete list of channels that are transmitted can be found by loading the M1 templates in the C125 Dash Manager.
Just stumbled upon this thread and am wondering whether the preference for dash over ECU logging really applies to those with development licenses on their M1 ECUs. In that case, I see no bar to setting up and transmitting to the dash via CAN whatever sensor data you choose. The logging rates and capacity I have on my M190 exceed those of my C125 (though I suppose the USB logging on the C125 has greater potential capacity), so I had been planning to acquire and log, for example, shock pots, via my M190. Appreciate any thoughts/advice.
That is correct that with a Build Licence you can add more channels to the CAN Transmit and setup suspension pots into the M1, but the payoff is a higher CPU usage on the M1 to do this, especially if the suspension pots are being logged at 1khz to obtain useful data. It may be that you have enough CPU overhead available to be able to do this without suffering issues, but if you look at your logging and see dropped data, then this is due to the M1 prioritising running the engine over logging due to a lack of available processor.
My preference for setting up a vehicle is to use the ECU logging for engine related functions, and the Dash for other vehicle channels.
If possible, I like to log at the device to which the sensor in question is directly connected. When you get into logging over CAN, your logging rate becomes limited by an additional factor, which is how fast a new CAN message can be sent out with new data. For slow moving items (temperatures, etc), this isnt really a problem, but for any sort of dedicated motorsport chassis tuning, sending the data out over CAN and having another device log it might be a bit limited. Do you think in M1 Build you could create can messages that were, say, the last 5 sensor values, and send them out in one message, possibly also with timestamps? Would have to get the receiving device to decode it, but would help.
It is possible, but you would use a lot of CPU and memory doing so.
The M1xx can log 1785 different parameters. If the one you want isn't in the list then go dash.
Have you looked at the list in Tune and spotted anything you might want missing?