Other Setup Guide for High-Downforce Cars v1.3

[Tim O'Glock]

Tim O'Glock submitted a new resource:

Setup Guide for High-Downforce Cars - beat every record with this one simple trick

I have decided to release my own setup guide for Automobilista. It focues on high-downforce cars and how they are affected by ride height changes. Among other things it explains how telemetry can be used to find the perfect ride heights of any car.

Below is a demonstration of the improvements that can be achieved within a matter of minutes by making use of the knowledge this guide equips you with. All I changed from the default setup are the ride heights, the thrid springs and the packers....

Read more about this resource...

 

[Tim O'Glock]

Tim O'Glock updated Setup Guide for High-Downforce Cars with a new update entry:

completely reworked the damper section

• completely reworked the damper section
• added an Excel-file for the calculation of damping ratios to the list of downloads
  
• added a MoTeC project to the list of downloads
  
• fixed some minor errors

Read the rest of this update entry...

 

[Tim O'Glock]

Tim O'Glock updated Setup Guide for High-Downforce Cars with a new update entry:

small update

• reworked the anti-roll bar section
• made small changes to the differential section
• added short explanation of bump and rebound to damper section
• rearranged parts of the aerodynamics section
  
• fixed minor errors throughout the document

I'm very happy with the current state of the guide, so don't expect any updates in the near future.

Read the rest of this update entry...

 

[MotherDawg]

Hey Tim,
I think you're wrong about the diff...
Nice work Bud! Thank You!
I'll post my tidbits here, like page page 4, 1.1 Tires, the text inside the parentheses in the last line of the 3rd paragraph: (increase pressure to increase temperature middle temperature).
I'm reading it now.

 

[MotherDawg]

page 4, 1.1 Tires, 4th paragraph: "Default tire pressures are usually set to very good values and fine tuning them is generally a waste of time"
That's a fairly big presumption... Frenchy here... assumption maybe? I'm presently doing a Formula Classic series in the MNRL, to spread my temps, more often than not, I need to increase the default pressures by around 1.0 psi. We are also doing a Brazilian StockCar series, in that one, at the front, I have to go up about a pound but 1 down at the rear.
To see if my setups are far out there, I download dozen of the from VXP and make a huge spreadsheet with them. Pressure wise, I'm well in the ball park but then again, some of these guys use out of this world pressures... probably for their single lap attempts.
I think tire pressures are directly related to how each of us go through turn so I feel you wording slightly restrictive. I also use telemetry and it shows me where I need to go.
I'm reading...

 

[MotherDawg]

1.1 Tires, last paragraph: "Camber makes very little difference in this game"
If you try 3-4 degrees of camber and 7-8 of caster VS 5-6 degrees of camber and 3-4 of caster, your temps spread is going to be all nice but you'll have a totally different car.
I work a lot with cambers in AMS, mostly to adjust the temp spread but together with caster, they do make a difference.

1.4 Engine, 2nd paragraph: "Always set brake map to the highest value"
I find this can severely diminish rotation during cornering. I sometime have to let the car breathe... even lift completely either to correct my entry speed or to adjust for a radius change. Having the engine map too high will negate some of that turn in.

Nah... Tim! Diffs again?
I'm not understanding your graphic so I fiddled with it... please tell me where I'm not getting it.

I'm still reading...

 

[MotherDawg]

2.1 Springs, 3rd Springs and Packers
First line of the 5th paragraph: "The combined stiffness of the front suspension in heave direction is the..."
"Heave"... That's way too British dude! Up, Down, Compression... Rebound?

2.2 Dampers, page 9,
"From this we can deduce whether a change results in more or less rotation in that phase of the corner"
Easy to say but reads... awkwardly. From my Canadian English, I would go with:
"From this we can deduce whether a change does result in more or less rotation in that phase of the corner"

I'm still reading... not finish typing here... checking out 2ζ√Kb*Mb

I just figured that the needed documents were actually links.
I been using Gringo's DAQ for a while now.
My MoTeC Project was from some other resource, I was looking for an AMS specific one. Thx Tim.
The spreadsheet... I was looking all over the place... could you colorize the links?
I would make them a lot more evident.
But hey, I found this one: www.izzeracing.com/Damper%20Calculators.xls
Izze Racing has some nice sensors!!!
And this... https://excel-works.com/manual?helpTopic=dySys2

I'm still reading...well calculating...

 

[Tim O'Glock]

I don’t have a lot of time, so I’ll keep my answers short.

page 4, 1.1 Tires, 4th paragraph: "Default tire pressures are usually set to very good values and fine tuning them is generally a waste of time"
That's a fairly big presumption... Frenchy here... assumption maybe? I'm presently doing a Formula Classic series in the MNRL, to spread my temps, more often than not, I need to increase the default pressures by around 1.0 psi. We are also doing a Brazilian StockCar series, in that one, at the front, I have to go up about a pound but 1 down at the rear.
To see if my setups are far out there, I download dozen of the from VXP and make a huge spreadsheet with them. Pressure wise, I'm well in the ball park but then again, some of these guys use out of this world pressures... probably for their single lap attempts.
I think tire pressures are directly related to how each of us go through turn so I feel you wording slightly restrictive. I also use telemetry and it shows me where I need to go.
I'm reading...
View attachment 300036

• Being within 1psi of the ideal value sounds pretty good to me...
• In general, the effect of tire pressures is much smaller than in some other games.
  
• I never said changing tire pressures is a waste of time, I said spending a lot of time fine tuning them is.
• Most of the setups on VXP are terrible.
• The ideal tire pressure depends mostly on the amount of load on the tire.
• Do you remember the AMS time trial challenge? The first round was the StockCar at Velopark. There were about 600 entrants, some of them very competitive sim racers that ran hundreds of laps. In the end, a guy running default pressures won. That’s how much tire pressures matter.

1.1 Tires, last paragraph: "Camber makes very little difference in this game"
If you try 3-4 degrees of camber and 7-8 of caster VS 5-6 degrees of camber and 3-4 of caster, your temps spread is going to be all nice but you'll have a totally different car.
I work a lot with cambers in AMS, mostly to adjust the temp spread but together with caster, they do make a difference.

Yes, they make a difference, but no change in camber is going to make the car significantly faster and that’s the only thing I’m interested in. The time trial challenge made that very clear.

1.4 Engine, 2nd paragraph: "Always set brake map to the highest value"
I find this can severely diminish rotation during cornering. I sometime have to let the car breathe... even lift completely either to correct my entry speed or to adjust for a radius change. Having the engine map too high will negate some of that turn in.

True, but you can always use the brake to help the car turn.

Nah... Tim! Diffs again?
I'm not understanding your graphic so I fiddled with it... please tell me where I'm not getting it.
View attachment 300048
I'm still reading...

The arrows don’t mean what you think they mean. They are simply the road forces that act on the car – nothing more, nothing less. I should probably mention that in the guide.

2.1 Springs, 3rd Springs and Packers
First line of the 5th paragraph: "The combined stiffness of the front suspension in heave direction is the..."
"Heave"... That's way too British dude! Up, Down, Compression... Rebound?

I’m not aware of any other word with the exact same meaning, but English isn’t my first language.

2.2 Dampers, page 9,
"From this we can deduce whether a change results in more or less rotation in that phase of the corner"
Easy to say but reads... awkwardly. From my Canadian English, I would go with:
"From this we can deduce whether a change does result in more or less rotation in that phase of the corner"

Agreed, your version is better.

I'm still reading... not finish typing here... checking out 2ζ√Kb*Mb

I just figured that the needed documents were actually links.
I been using Gringo's DAQ for a while now.
My MoTeC Project was from some other resource, I was looking for an AMS specific one. Thx Tim.
The spreadsheet... I was looking all over the place... could you colorize the links?
I would make them a lot more evident.
But hey, I found this one: www.izzeracing.com/Damper%20Calculators.xls
Izze Racing has some nice sensors!!!
And this... https://excel-works.com/manual?helpTopic=dySys2

I'm still reading...well calculating...

Yes, I should really make the download links easier to find.

 

[MotherDawg]

WoW !
Awesome Tim,
Thanks for taking the time and for any other inquiries I might have, no rush, when you find the time is fine by me.

Just to make sure you caught it from my first post:
page 4, 1.1 Tires, the text inside the parentheses in the last line of the 3rd paragraph :
(increase pressure to increase temperature middle temperature)

Most of the setups on VXP are terrible.

Mouhahahaa... thought so myself !

no change in camber is going to make the car significantly faster

Ok, noted.

you can always use the brake to help the car turn.

That is where I'm at in my driving...

They are simply the road forces that act on the car

So they are not the results of the action of the quantity of Lock, ok.

Heave, Surge, Sway... I'll go to bed less dumb tonight. Thx
It's probably standard in an English language curriculums but I live in Québec so I followed a French curriculum... and I remember "zilch" from my physics courses.

Ok,
From point 3.0 down, up to now, I haven't found anything, all well written.

Top of page 14, you write about creating 3D plots with the results. Suggestion here, you could elaborate on that, describe some method to achieve those graph.

Now, Motec Automobilista HD Project
Where does that project come from?

From the present Automobilista_DAQ_Plugin_Setup_1.3.2_v10, the DataAcquisitionPlugin.ini logs the pedal's positions as:

Brake Pedal Position
Clutch Pedal Position
Throttle Position

The Throttle has an alias named: Throttle Pedal Position
That "HD" project is quite different than the one I was using, I'm still cleaning that one, there were a bunch of "Lamda" and "Mixture" channels that were N/A.
In that HD project, I have many channels that are also N/A.

Did I mess up my Motec install or are you using a custom DataAcquisitionPlugin.ini ?

In "General", "Track Report", the "Throttle Pedal Position" was set to "Throttle Pos".
Same for "Delta Time" worksheet, "Throttle Pos". On that worksheet, when I load 2 sessions, the Delta Time channel shows a delta graph but the Delta Time Derivative stays empty.
In the Tyre Temperature woorksheet of the Tyres workbook (?), the channels use "Tire Temp - FL - I" were the actual channel name is "Tyre Temp FL Inner".

As you can see in the screen, The Throttle channel name is wrong and the Damper Velocity graphs stay empty. And so on... where the Beef ?

I wanted the list them all here but there are just too many. I'm rebuilding it for what the DAQ plugin install is giving me. If I'm all ok, I'll have a cleaned up workbook in a couple of days.

What do you use ?

 

[Tim O'Glock]

Just to make sure you caught it from my first post:
page 4, 1.1 Tires, the text inside the parentheses in the last line of the 3rd paragraph :
(increase pressure to increase temperature middle temperature)

Yes, I saw it. Thanks for reporting it.

So they are not the results of the action of the quantity of Lock, ok.

No, you are correct, they are the result of the steering input.

Top of page 14, you write about creating 3D plots with the results. Suggestion here, you could elaborate on that, describe some method to achieve those graph.

Unfortunately, I don't know any free software that can create such plots. It's difficult because most software need a complete data set (there have to be discrete values of x and y as well as a value z for all of these points). Software that can handle imcomplete data sets are typically used in design optimization. Google the terms metamodel and response surface.

Now, Motec Automobilista HD Project
Where does that project come from?

From the present Automobilista_DAQ_Plugin_Setup_1.3.2_v10, the DataAcquisitionPlugin.ini logs the pedal's positions as:

Brake Pedal Position
Clutch Pedal Position
Throttle Position

The Throttle has an alias named: Throttle Pedal Position
That "HD" project is quite different than the one I was using, I'm still cleaning that one, there were a bunch of "Lamda" and "Mixture" channels that were N/A.
In that HD project, I have many channels that are also N/A.

Did I mess up my Motec install or are you using a custom DataAcquisitionPlugin.ini ?

In "General", "Track Report", the "Throttle Pedal Position" was set to "Throttle Pos".
Same for "Delta Time" worksheet, "Throttle Pos". On that worksheet, when I load 2 sessions, the Delta Time channel shows a delta graph but the Delta Time Derivative stays empty.
In the Tyre Temperature woorksheet of the Tyres workbook (?), the channels use "Tire Temp - FL - I" were the actual channel name is "Tyre Temp FL Inner".

As you can see in the screen, The Throttle channel name is wrong and the Damper Velocity graphs stay empty. And so on... where the Beef ?

I wanted the list them all here but there are just too many. I'm rebuilding it for what the DAQ plugin install is giving me. If I'm all ok, I'll have a cleaned up workbook in a couple of days.

What do you use ?

I created this Project.

I use the default DataAcquisitionPlugin.ini. Unfortunately, the person who uploaded the DAQ Plugin to RD suggests to change the names of some channels to make the telemetry files work with his project. I didn't do that because I'm not using his project. I'll attach my DataAcquisitionPlugin.ini to this post.

Delta time and its derivative are very buggy. Sometimes they don't work at all, sometimes they can be fixed by changing the amount of smoothing.

You can also use the built-in delta time by pressing F3. It should always work, but it can't be used like a regular channel.

 

[MotherDawg]

Way kewl dude. Thank You !

 

[Tim O'Glock]

Tim O'Glock updated Setup Guide for High-Downforce Cars with a new update entry:

New MoTeC Project and Quick Start Guide

• added a few useful features to the MoTeC project
• added a quick start guide that explains some of the most important features of the MoTeC project
  
• fixed minor errors

Read the rest of this update entry...

 

[Niels_at_home]

Nice to see things taken seriously. Pressure and temperature are of some effect. Having 'even' tire temps or having the middle temp be in between the outer temps might not be as important as being on the right pressure.

The average temperature is used to compute grip, so if your I/M/O is 100,90,90, the average temp is 93.3. If the tire has an optimal temp of 95, you could add pressure until you are at 100/95/90, but perhaps this extra pressure looses you more grip than the now optimal temperature adds.

The more load there is on the tire, the more tire pressure it needs to reach maximum grip. With high downforce cars this might mean in hairpins your optimal pressure is 1.1Bar, but in a flat out corner it might be 1.6. Sadly drivers are not allowed to bring a bicycle pump to adjust the pressures a few times per lap..

 

[Tim O'Glock]

You are absolutely correct. Setting up a car is about finding good compromises. The goal is always the minimization of lap time, never the optimization of a single parameter or corner.

 

[Tim O'Glock]

It seems there is some confusion about what bringing the middle tire temperature between the other two actually achieves. It is not about getting closer to the ideal tire temperature and it is not because a temperature spread improves grip. Instead, this method is all about making the tire work more evenly across its width. The middle temperature provides us with an indication of how evenly we are using the tire. If the pressure is too low, the middle tire temperature decreases relative to the other two. If the pressure is too high, the middle temperature increases relative to the other two. We can adjust the pressure accordingly.

Does this method result in the perfect tire pressures? No, absolutely not, but it typically results in a good compromise. There are of course exceptions and that is why we should never blindly follow an approach like this without verifying that it actually works for the car and track we are currently using.

The average temperature is used to compute grip, so if your I/M/O is 100,90,90, the average temp is 93.3. If the tire has an optimal temp of 95, you could add pressure until you are at 100/95/90, but perhaps this extra pressure looses you more grip than the now optimal temperature adds.

This is a good example of how we have to find tradeoffs between different parameters, but it is a bit flawed. Adding pressure changes all of the three temperatures. The middle temperature may increase by adding pressure, but the other two will decrease. Overall, this will result in an average temperature that is slightly lower than before.