Your Data Driven

ACC Tools provides Your Data Driven to help you optimise your tyre setup using the methods taught by Samir Abid of Your Data Driven. Two of the tools he provides for free using Microsoft Excel spreadsheets have been replicated in ACC Tools with his kind permission.

We recommend you read two of Samir’s posts to fully understand how these tools work.

• How to set you racing car tyre pressures perfectly (every time)
• Guide to interpretings tyre temperatures in motor sports

Selector Panel

Like many of the tools in ACC Tools the Your Data Driven tool requires you select a Track/Car combination for analysis. In addition this tool requires you to select a specific lap. The lap is used to provide the telemetry data that is used in calculations that avoid the need for you to manually enter it.

Each time you change a selection, analysis is recalculated and fields are updated.

The selections you make along with some of the inputs you provide are saved so that the next time you select the same Track/Car combination they can be restored.

Tyre Pressure Optimiser

The first of two tools provided within Your Data Driven is the Tyre Pressure Optimiser. This can be used as an alternative to the Tyre Pressure Calculator provided by the Race Engineer tool. It differs in that it does not simply use a delta to suggest tyre pressures. Instead it uses a slightly more complex formula to calculate them.

There are six steps to follow with this tool.

Step 1

Enter the tyre pressure you want to acheive once tyres are up to temperature for each wheel. In ACC the recommended hot tyre pressure is 26 to 27. The default of 27 is entered for you the first time you choose a Track/Car combination.

Step 2

Enter the initial scaling factor you want to use for each wheel. The Scaling Factor is typically between 1.2 and 1.5. It is normally calculated as the target hot pressure divided by the cold tyre pressure. However in the Your Data Driven tools it is used inversely to calculate the initial cold pressures you should start your optimisation activity with. The default of 1.25 is entered for you the first time you choose a Track/Car combination.

Step 3

In ACC with the Track/Car combination selected enter the Initial Cold Setting suggested for you for each wheel in the Setup Screen. These values are calculated for you based on the inputs in the previous two steps.

Step 4

Head out on track in ACC and drive at least 5 consistent laps to get the tyres fully up to temperature. Stop as soon as you cross the finish line and enter the Setup Screen.

Enter the actual hot pressures shown in the ACC Setup Screen for each wheel.

This will trigger a re-calculation of the analysis and suggest the new cold tyre pressures you should try.

Step 5

The Actual Scaling Factor is displayed for you. This is for information purposes, but could be used for future optimisations

Step 6

Return to the ACC Setup Screen and enter the Suggested Cold Pressures.

Rinse and Repeat

Repeat steps 4 to 6 until you acheive the target hot pressures.

Temperature Optimisation

The Temperature Optimisation section of the Tyre Pressure Optimiser allows you to get adjustments to the Suggested Cold Pressures for a different session where conditions are different.

For example, you optimise your tyre pressures using Tyre Pressure Optimiser during a Practice session where the Ambient Temperature is 26 and the Track Temperature is 30. You progress to Qualifying and notice the Ambient temperature has gone up to 28 and the Track temperature has gone up to 32.

Enter 26 and 30 into the Ambient and Track fields labelled with Test Run. Enter 28 and 32 into the corresponding fields labelled Adjusted.

As shown in the screenshot above this will populate the read only fields labelled Adjustment. Apply these adjustments to the Suggested Cold Pressurs calculated for the previous session and set them in ACC before starting your qualifying session.

Tyre Temperature Optimiser

The second tool provided within Your Data Driven is the Tyre Temperature Optimiser. This can be used to further optimise tyre pressures and Camber to ensure the temperature spread across each tyre is optimal. Sadly most people rely on the so called Meta Setup principle identified soon after ACC 1.9 was released and apply maximum Camber on all wheels.

Target Window

The first step in using this tool is to set the Target Window for tyre temperatures. In the first field labelled Tyre °C enter the tyre temperature you would like to acheive.

The optimal tyre temperature for ACC is 70 to 100 degrees Celcius. The default of 80 will be entered for you the first time you select a Track/Car combination.

The second field allows you to set a tolerance window of plus or minus a few degrees. The default of 5 will be entered for you the first time you select a Track/Car combination.

With the defaults set this tool will consider tyre temperatures between 75 and 85 as acceptable.

Camber Temp Spreads

The next step is to set the maximum spread of temperatures across the surface of tyres. The recommended maximum spread from inside to outside should be 15°C. The Tyre Temperature Optimiser allows you to set a different maximum level for front and rear. The defaults of 8 and 4 are entered for you the first time you select a Track/Car combination. These values are used to remaind consistent with the tools provided by Samir Abid.

Actual Temperatures

With the Target Window and Camber Temp Spreads set, enter the actual tyre temperatures from the Setup Screen in ACC after driving at least 5 laps to ensure tyres are up to temperature.

Enter the values labelled O in ACC into the fields in the Outside column, the values labelled M in ACC into the fields in the Middle column and the values labelled I in ACC into the fields in the Inside column.

The rows and columns are organised in the way a race engineer would work around a real race car staring with the front left and working anti clockwise around the car. That is Front Left, Rear Left, Rear Right and finishing with Front Right.

Analysis

With everything entered and setup the Analysis section will help you identify any adjustments you might need to make.

Temp Profile

The first column of the Analysis section displays a graphical representation of the angle of the surface of the tyre relative to the ground and centre of the car.

Inflation OK?

This column of the Analysis section indicates whether the tyre is Over inflated, Under inflated or OK. Typically an over inflated tyre is hotter in the middle portion than the outer portions. While an under inflated tyre is typically colder in the middle portion than the outer portions. However this tool will also indicate Over if all portions of the tyre are above the target window and Under if all portions of the tyre are below the target window.

Camber OK?

This column of the Analysis section indicates whether the Camber of the tyre is appropriate based on the maximum spread configured. Typically for a properly inflated tyre the temperature spread will increase as more negative Camber is applied. This column indicates whether the spread is Too Little or Too Much and will show the actual temperature spread in degrees Celsius.

In Window?

This column of the Analysis section indicates whether the average of the Inside, Middle and Outside temperatures are within the Target Window configured. It displays the average temperature in degrees Celsius.

Balance

These columns of the Analysis section indicate whether tyre temperatures are balanced using averages. The left column displays the Front to Rear balance while the right column displays the Left to Right balance.