The online racing simulator
Advanced Setup Guide
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(46 posts, started )
Advanced Setup Guide
Well I'm sure many of you are familiar with the basic setup guide on the BR website.

So I thought, since I've been doing lots of reading into all this, that I could write a more in-depth setup guide, for those of you that REALLY want to know what it all does.

You can now get the latest version at my website. Here's a direct link.

Flash and PDF versions are available.

Last update: Revision 2e for LFS 0.5P
Looks great on the first view. Think I'll study "this" the next days... or weeks^^...
This is absolutelly Bobbish. ! Really great work there, helped me to understand clearly many things
For the "wheel turn" and "wheel turn compensation" settings..

You could add a small section for people with Logitech Driving Force Pro's (or any other wheel with 900 degree rotation)

Also list the correct steering lock to lock of all the cars in LFS S2.. (tested myself to find out)
Cars that use 720 degrees of rotation:
XF GTI, XR GT, XR GT Turbo, RB4 GT, XFO Turbo, LX4, LX6, UF1000, UF GTR, XF GTR, FZ50, Raceabout..

Cars that use 540 degrees of rotation:
XR GTR, XFO GTR, FZ50 GTR

Cars that use 450 degrees of rotation:
Formula XR, Formula V8

Car that uses 270 degrees of rotation:
MRT5


For people with a DFP- it is possible to get completely realistic lock to lock settings in LFS easily..

One way gives you "force feedback end stops" when you get to the end of the rotation of the wheel on screen in LFS.
The other way is easier, but you don't get the force feedback end stops that the new Logitech 4.60 drivers give you.


Easy way (set and forget):
Since the largest lock to lock in any car in LFS is 720, set the DFP to 720 degrees in the DFP control panel.

Then set the "wheel turn" setting to 720 and set the "wheel turn compensation" to 1.00

this will give you linear steering in all cars, but will only give you the end stops for the wheel in cars with 720 degrees lock to lock. After that the force feedback does not respond.


The way I do it to get end stops with all cars and what seems to be more accurate force feedback:
For whatever car you are using, chose that lock to lock in the DFP control panel..
*You can easily press SHIFT + F4 to jump out of the game while in the pits, set the Logitech control panel, and jump right back in the game.. It takes about 10 seconds time and there is no need to re-calibrate.

Say you are in the FZR- set DFP CP to 540, in game set "wheel turn" setting to 540. Keep "wheel turn compensation" to 0.00.. (always leave wheel turn compensation to 0.00 when doing it this way.
That's it. Then you get true linear steering and take advantage of the FF end stops that the DFP driver gives you. I think the FF feels better too.


This might help because in the guide there is a statement that is made that does not pertain to the DFP.
Quote :"Steer Compensation 0.0 > Not realistic at any time, but absolutely linear right through the range."

With the DFP that statement is false, because of course when wheel turn compensation is set to "0.00", and the DFP is set to same rotation as the car in game... it is exactly realistic.. A beautiful thing too..


That would be a good addition, and create less confusion for people who just got a DFP... I had to figure it out on my own, buying a DFP coming from a Momo racing.. I would have appreciated a guide like that, and it would have saved me a LOT of time. :cromo:
I'm going to give the guide another going over some time this month, I'll add that info, thanks.
Quote from Bob Smith :I'm going to give the guide another going over some time this month, I'll add that info, thanks.

Very cool! Thanks!
Quote from BWX232 : everything he said

That is absolutely amazing! I thought my DFP was pretty well sorted but this just transforms it. It feels so damned real and you're right, the FF IS better. How this information has been such a long time coming I don't know. Bloody good job!
Quote from Doorman :That is absolutely amazing! I thought my DFP was pretty well sorted but this just transforms it. It feels so damned real and you're right, the FF IS better. How this information has been such a long time coming I don't know. Bloody good job!



Try this- Leave the profiler off- keep everything at default values in there-

Go to- Windows control panel/ game controllers.
Make a shortcut to desktop for easy access if you want.

Try these settings:


And then adjust the FF in game with the < and > buttons.. Some cars, like the UF1000, you may want up to 100 FF in game, some cars as low as 30- whatever feels right.
Quote from BWX232 :

Try this- Leave the profiler off- keep everything at default values in there-

Go to- Windows control panel/ game controllers.
Make a shortcut to desktop for easy access if you want.

Try these settings:
http://driverheavenuploads.co.uk/BWX/LFS-DFP.png

And then adjust the FF in game with the < and > buttons.. Some cars, like the UF1000, you may want up to 100 FF in game, some cars as low as 30- whatever feels right.

Exactly the settings I already have. Have to leave the profiler running as I have a load of buttons mapped to it. i.e. shift+F, F1-4 trackIR centring etc
Yeah if you map buttons I guess you have to leave profiler on.
OK updated, revision 2d is now loaded and ready to rock 'n roll

Changes to the suspension, differential, gearing and downforce sections, amounting to 1669 more words, three more pictures, two more diagrams and one more table. Net result: 4 more pages of deliciousness.
hi bob its a great guide that u have done, helps a lot but im having a bit of trouble finding where i can see some of the stuff that u say in there, i have searched in the game but didnt found.... i know its sounds noobish but i just cant find them.
I do understand everything u say in there, but o cant find the stuff to change it and make a good setup... i have downloaded all the 3 other programs that u have recomended the lfs setup analyser,f1,and the gear ratio caulculator.

Pliz help this lost fella.....

thx for the great guide

Rod
Bob, I learnd much from the guide, helped me to start to create own setups. The best part I learned is in my signature
I have a question regarding suspension frequencies, sparked by recent discussions around my suspension calc.

In your guide, you say optimum frequency is around 2 Hz per 1000 Kg of car mass. Does this mean that on a front or rear-only basis, the optimum frequency is 2 Hz per 500 Kg?
eeeehhh yes and no.

The 2Hz figure is for a car of around 1000kg, so on average that's going to be ~250kg per wheel. So if you were just looking at the rear (being half a tonne), then yes you're still using 2Hz as a base figure.

The optimum is not 2Hz per tonne either, merely that for vehicles around a tonne that 2Hz is the optimum IRL. LFS seems to favour higher frequencies. I don't know how the optimum changes regards to vehicle mass (other than the lighter the car, the higher the frequency) - in other words I doubt it's a linear relationship. I would have thought by the time you're down to a 500kg car you'd be the optimum would be more like 2.5Hz. However again that's for real life, in LFS you'll be higher still.

And then that's only for cars without downforce. Like I explained, cars with downforce need stiffer springs for two reasons, one they reduce ride height and frequency with speed, so in order to get good results at race speed the springs need to be too stiff when stopped (i.e. in the garage). Also body roll can mess up the aero of the car (something I don't think we have to deal with in LFS - yet), another reason for increasing stiffness. I've never read a figure for them (F1 cars aside) but if you want a starting point I'd say 3Hz (again for a car around a tonne).
Quote from Bob Smith :eeeehhh yes and no.

The 2Hz figure is for a car of around 1000kg, so on average that's going to be ~250kg per wheel. So if you were just looking at the rear (being half a tonne), then yes you're still using 2Hz as a base figure.

The optimum is not 2Hz per tonne either, merely that for vehicles around a tonne that 2Hz is the optimum IRL. LFS seems to favour higher frequencies. I don't know how the optimum changes regards to vehicle mass (other than the lighter the car, the higher the frequency) - in other words I doubt it's a linear relationship. I would have thought by the time you're down to a 500kg car you'd be the optimum would be more like 2.5Hz. However again that's for real life, in LFS you'll be higher still.

And then that's only for cars without downforce. Like I explained, cars with downforce need stiffer springs for two reasons, one they reduce ride height and frequency with speed, so in order to get good results at race speed the springs need to be too stiff when stopped (i.e. in the garage). Also body roll can mess up the aero of the car (something I don't think we have to deal with in LFS - yet), another reason for increasing stiffness. I've never read a figure for them (F1 cars aside) but if you want a starting point I'd say 3Hz (again for a car around a tonne).

2 Hz per tonne was the wrong phrase--I know that frequency decreases with increased weight. Knowing that the relationship is not linear is good though--it won't change how the program works, but it will change how I use it.

When it comes to downforce, I calculate suspension frequency with the downforce in effect. Since the car "weighs more" with downforce, I base my spring rates on the increased weight. That way the car acts "normal" when it's at speed. That the frequency will increase at low speed is understood--but I measure downforce using the average speed I have in corners, so I'm not going to be going significantly slower except in the pits, where the suspension isn't very important. Of course this means at high speed the frequency is actually too low, but in that case I'm probably driving a straight line and again a perfect suspension isn't very important.
where is the basic setup guide? i have no clue what BR is i need the basic before this makes sense lol
There are links to other guides on one of the first pages of the advanced setup guide.

Making a much more compact guide that doesn't go into too much detail might well be appreciated by others though. I'll think about it.
Some small changes in revision 2e, namely corrects the spring stiffness with downforce bit. Also a little more information on setting up the clutch pack LSD, parallel steer and torque bias.

Edit: I've updated the WIKI too now.
Hey man, I can't seem to see your super cool sight. Is it still up? Maybe a direct load of pdf would help? THanks a lot dude.

ChiShiFu
Quote from ChiShiFu :Hey man, I can't seem to see your super cool sight. Is it still up? Maybe a direct load of pdf would help? THanks a lot dude.

Ah thanks for pointing that out, I changed ISPs a couple of months ago and forgot to change the URL to point to my new webspace. Is sorted now.
If you increase front rebound, then the front will rebound SLOWER.

I think he did make mistakes on anti-roll bars, by claiming they reduce load transfer, and therefore claiming that infinitely still bars would be ideal on a smooth, flat track because of tyre load sensitivity. Unfortunately, the opposite is true - you want the MINIMUM bar you can get away with to retain wheel camber control in roll (and, potentially, corner ride height changes), thus keeping the cambers good and load transfer as small as possible to maintain grip through tyre load sensitivity.
Funny this thread should be bumped now, while I'm slowly rewriting the guide. There are no doubt many things I could explain better and more accurately now.

Anti-roll bars indeed do not directly reduce lateral weight transfer, but they do reduce body roll, which reduces secondary weight transfer (from lateral CoG shift). I'm still thinking that on a perfectly smooth track, without bumps, you don't even have a real need for suspension, so if you do have it, maximum anti-roll bars is still the way to go. Of course having suspension still means you can use it to tune handling.
But for tyre load sensitivity you want the LEAST load transfer possible. Always; bumpy or smooth.
For camber control you want as much as you can get.
Additional load transfer from body roll is pretty negligable on most cars used for racing, although I don't doubt a proper analysis should consider it anyway.

Up to a point, camber control is considered more important than load sensitivity, so cars run a fair amount of bar to keep the tyres at the right angle. Too much front bar, for example, increases understeer as the gains in camber control (i.e. less roll generation for a given lateral acceleration) do not match the losses in load sensitivity grip. Too little front bar will give understeer too, due to lots of load sensitivity grip, but at the expense of camber control (which will have an effect on tyre wear and temperatures too). It will also reduce response, but just considering a steady state cornering situation you can ignore response times

The better your suspension (i.e. the better the camber control in roll) the softer you can run your ARBs. For years single seaters have run no rear ARB because the camber curves at the heavy, stiffer (in bump) end didn't need assistance, and more grip was generated with a lower roll stiffness (although other factors come into it as well of course).

My car runs a rear bar though, because it's old and out-of-date.

And I've not won a real race, so what do I know

Edit: What DO I know - the above, as I intended it, is rubbish.

Whilst it is true you want the least load transfer, load transfer is effected by CoG height, track width and accelerations. Stiffen your anti-roll bars and you'll have the same load transfer if the other stuff stays the same. So I was talking rubbish. What bars CAN do is alter the load transfer at each end, even though the total front + rear remains the same. A stiffer front bar will have MORE load transfer, which will cause understeer via load sensitivity, and will REDUCE load transfer by the same amount at the back, increasing grip and reducing slip angles (which increases understeer).

So, the bars control body roll, which in turn controls camber recovery. More bar = less roll = more static camber curves (which may or may not be a good thing, but it's likely to be more good than bad). Too stiff a bar (assuming non-adjustable, and at the right ratio fore:aft) will merely cause less body roll, quicker responce and a certain amount less 'feel'. Too soft = more body roll (which may cause less grip through camber curves), slower responce and more 'feel'. The balance is struck when roll, feel and speed of responce are okay.

If you have understeer, soften the front or stiffen the rear, depending on whether you'd rather have more roll (feel) but slower response from the front, or less roll and a quicker responce from the back. Swings and Roundabouts really, with no 'right' answer. It also means that my concerns about having too stiff a front:rear ratio in roll won't be a problem from a balance point of view, as I can soften the front a bit to match the softer rear. But I'll need to buy a stiffer rear bar if we get too much roll. The question is: how do you tell if you have too much body roll (and not confuse it with insufficient negative camber?)
Quote from tristancliffe :But for tyre load sensitivity you want the LEAST load transfer possible.

Of course. So, although body roll usually only contributes something around a tenth of the weight transfer of lateral acceleration, there is still benefit to reducing this roll (assuming front and rear bars are adjusted in proportion).
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Advanced Setup Guide
(46 posts, started )
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