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MoTeC telemetry for rFactor.

The start of the guide will concentrate on the setting up and most basic usage of the MoTeC Telemetry program. Throughout the rest, we will try to introduce MoTeC where we feel we have understood it as it relates to driving and, ultimately, racing.

To start with, it should be understood that telemetry is a very personal, individual thing. Readouts from laps driven by one driver may look very different than readouts driven by anyone else, even when using the exact same car setup. Each driver has their own style. While some drivers are late brakers, others like to accelerate early, left-foot brake, drift, or any other combination of getting a car around a corner. A select few can even manage to combine all of those techniques to find the quickest time possible around a given corner.

In order to best understand how MoTeC may be able to aid a driver, we will assume that everyone following this guide will start off with the default setup at a track most of us should be pretty familiar with. We will be concentrating, initially on the BMW E90 mod for rFactor, though the principles should be the same for all mods, tracks and also across most racing car simulators.


Note that we said simulator - for that is what we are discussing here. rFactor is a game, but it is also a simulator and people who race competitively are taking part in a new kind of sport. A simulator is a program that takes real world physics into account and tries to emulate those physics (no matter how well or how badly) in the gaming environment by using real world values and constants. And arcade game, by contrast, is one in which the program's variables are tweaked to create a model which makes for an enjoyable escape, often with fantasy and futuristic vehicles. And many of them are indeed very enjoyable - we should not be sim-snobs!

MoTeC is a real racing car telemetry program, used in the real world by actual racing teams. rFactor is a simulator which uses values found in the real world in the game. MoTeC and rFactor are compatible. Thus rFactor is a simulator. Not only that, but real drivers - even Formula 1 drivers and teams - have used the special version of rFactor for off-season and in-season testing, and to train rookie drivers.

Installation of MoTeC

Now that the introductory blurb is over, let's move on to the actual installation. The first thing you have to understand is that the Data Acquisition Plugin is an add-on that you have to use so that MoTec can access the lap data. The second thing to understand is that MoTec's latest version of the software is apparently not compatible with rFactor (or the Data Acquisition Plugin).

MoTeC Pro software (download version i2 Pro V1.03.0106 17MB dated Oct 22nd 2009 15:31)

Data Acquisition Plugin (rfactorcentral)

Data Acquisition Plugin Patch (nogripracing)

Go ahead and install MoTec into it's default location (C:\Program Files\MoteC or C:\MoTeC). You don't have to bother with the MoTeC folder after this, though it does have some default projects in it. We'll be uploading a project for us all to use though.

Now install the Data Acquisition Plugin. This should go into your rFactor folder (C:\Program Files\rFactor). It automatically creates two new folders: C:\Program Files\rFactor\PLUGINS\rFactor Data Acquisition Plugin and C:\Program Files\rFactor\USERDATA\LOG\MoTeC. Feel free to let the program check for updates if you are connected to the Internet. Then install the Data Acquisition patch.

Go to the rFactor directory and edit the file called DataAcquisitionPlugin.ini with Windows Notepad. Edit the line that refers to samples per second. Change it from 10 to 50.

And that's it!

... or is it?

Well, not really. In order to use telemetry software, you need to be able to understand telemetry data. Any engineers, mathematics or physics experts amongst us will probably have a head start. The basics are reasonably simple though. Setting up MoTeC is difficult only because you're not used to the program yet.

Acquiring telemetry

To activate the Data Acquisition Plugin, simply press Ctrl-M any time when you're in the pit lane or on track, and the data will start logging. Ctrl-M also toggles logging off again. When toggling, a female voice will let you know the status in English.

Now run say four to seven laps of your selected track (after activating the plugin) and then head back to the pits or press Escape, and Alt-TAB to the desktop.

I've attached a MoTeC Project to this post. Just extract it to your rFactor folder. Don't worry about the double folder name "Try". This is one I've been "trying" to compile together. I'll make updates as I learn more, and add more sheets to it, so you can just get them, delete the older one and extract the new one to the rFactor folder.

Attachment: Try.rar [238.55 KiB] Downloaded 10 times

Once you've extracted it, navigate to your rFactor folder: C:Program Files\rFactor\Try\Try and double-click on the file named Project.mtcprj. On some people's PCs, the file will just show up as "Project", if you have not chosen to show the file extensions. If you've installed MoTeC correctly, it should have a MoTeC icon beside it with "i2" in it on a red background.

Now open a log file by pressing the yellow folder icon on the top left of the Motec window, or by going to File ---> Open log file... In the window tree on the left hand side of the new window that pops up, navigate to C:\Program Files\rFactor\UserData\LOG\MoTeC. It might take a few seconds for the files to display the first time you open MoTec. You should find your recent laps here under one file labelled with the track name.

Double click on it so that it is added to the list of selected files at the bottom, and then press Open.

Initially, the laps you have loaded will probably be hidden. Click on the icon on the left that says "Data" and a window will pop out. You can make it permanent by clicking on the little pin icon ("click to dock window").

Now you can look over your laps data by clicking on which ever lap you like on the left hand side, and by clicking on the tabs near the top labelled 1: Tyres 2: Engine 3: Brakes and so on...

To the left of the Tyres tab, there is a drop-down button, which should read "MotecGeneric Template. I've added another 'Workbook' called "Suspension" as well. More about that later though.

For now, take a look at your lap data. Click on the 'Engine' tab. At the top of that 'Worksheet' there is a section that tells you your engine and oil temperatures for your fastest lap of that session. You can move the cursor (a vertical line) about by clicking anywhere on the lap, from left to right. The values at the left change according to what the data was at that point in the lap. You can hold the cursor and pull it along to any point on the lap too, to see how the values changed over time. You can also press the 'Play' button in the icons at the top, and MoTeC will run through the lap in real time, starting from your cursor position.

The values across from the labels Engine Oil Temp and Engine Temp in orange and blue are the max, min and average values for the lap. You can double-click on the max and min ones to get the cursor to move to that point automatically.

Try having a look at the brakes tab (worksheet) and see what your maximum brake temperatures for each brake. These can be important in determining the sizes of your brake ducts and engine duct (radiator size).

MOD Values

That brings us neatly to where we find the optimum temperature values, and other information, from what ever mod we happen to be using...


One of the most important concepts in racing is grip. Therefore the tyres are of utmost importance. The tyres are the only point of contact with the track. Everything - every single component of the car - affects the tyres in some way or another. There are two main concerns with regard to tyres: temperature and pressure. With regard to pressure, we can talk about the pressure inside the tyre versus the pressure put on the tyre by weight and movement. These two forces also affect the temperature. Tyres are made of a rubber compound and, when exposed to heat or cold, rubber deforms (expands or contracts) and pressure inside the tyre also changes, resulting in further deformation. In order to achieve maximum grip, the surface area of contact between the tyre and the track surface must be at maximum. If the tyre is deformed by heat or cold (or non-optimum pressure), less surface area will make contact with the track, resulting in less grip. (see the graphics below)

You can see that an over- or under-inflated tyre doesn't make maximum contact with the track surface.

To understand the shape of a tyre, caused by temperature, sensors are placed at both the inside and outside edges, and in the centre of the tyres.

The thing about racing is that the temperature of each tyre can vary enormously throughout a race, and even a single lap. Tyres have an optimum temperature at which they operate at an optimum grip level (more about this later). We can measure this in all sorts of ways, however, it is important to realise that track straights are relatively unimportant with regard to grip. Tyres are heated by traversing curves, by pressures and friction. So we could take an average temperature of the middle, inside and outside of each tyre during a lap. It would be more prudent, though, to take readings at the corners in which each tyre heats up the most - these are the corners in which the grip values are being tested to their maximum: the times at which the driver relies on grip the most.

Now this may sound contradictory. BrunoB suggests that the actual temperature (and pressure) values are unimportant in comparison to the differences in temperature inside to outside. I have heard various ranges suggested as being optimum, from 5 degrees (Celsius) difference across the tyre, to up to 20 degrees. It seems to me that around 6 degrees difference from inside to outside offers the optimum grip range. So, for a tyre said to have an optimum operating temperature of 90 degrees, the optimum temperature values would be inside (hottest): 93, middle: 90 and outside: 87 degrees. However, the middle value might not actually be 90 degrees in practice, as we measure the tyre temperatures at their hottest around its most stressful corner. So getting values of 101; 98 and 95 may be optimal. The temperature of the tyre will drop off during straights or going around opposite corners, during which the pressure and friction is transferred to the tyres on the other side of the car.

It might be worth noting at this point that it appears a tyre slightly hotter than optimal will offer better grip than a tyre which is slightly cooler. To put it another way, the drop-off in grip level is at a higher rate when the tyre is cooler than operating temperature. Here is an example of the entry in the MMG 2007 mod for the Bridgestone "Soft" compound:

GripTempPress=(2.528, 1.421, 0.845)  // Grip effects of being below temp, above temp, and off-pressure (higher number -> faster grip dropoff)

Notice that the first value - that for the grip drop-off affected by temperature variance - is higher. The helpful comment in the file tells us that this value relates to a tyre which is below (optimal) temperature. The drop-off value for a tyre above optimal is lower.