@shotglass :

Well, I do think that you can drive a 140 hp RWD car without that much power oversteer, even if it doesn't weigh that much. eg. a Mazda MX5. Its much easier to control than the XF GT.

The FZ50 is comparable to a Porsche. And a lot of old people drive Porsche. It propably will step out if you really floor it in a corner. But you can put an unexperienced driver in a Porsche and let him drive around a track.
In most cases he won't crash it
Even if he is young and not as scared as old people.

If you put an unexperienced driver in an FZ50 in LFS, he certainly will spin out in first or second corner, even if he drives careful and doesn't try to be fast ...

But as I said I am not really sure about it. I just think its more like in rFactor, where you only have to be a good driver if you really push the car in the corner. Then it will step out. Not as fast as in LFS.

http://www.lfsforum.net/showthread.php?p=125133#post125133

Look there for raf analyser wheelspin. There is a lot of wheelspin going on at the start in a FZ50.

I do think, a formula 1 car will start better because it has a TC which helps. Most GTR cars haven't got a TC (like in LFS).
So in real life a GTR car will lose from the start against a formula 1 car with TC setup.

@BWX : Thanks
I know, that a lot of people experience the wheel spin problem and see it. I am not the only one

bal00 : Interessting point of view. I don't know what the problem is yet. I just analyse the result.

I am not sure if a good start really can produce better times, than with full throttle at all. Haven't experienced that yet.
If it does, it won't be much better than starting with full throttle. Not significantly at least.

@bob : I tested it with 6% TC and 10 m/s speed and the result was again worse than without TC : 5.78
Wheelspin has 5.72 ...

Wheelspin when starting a FZ50 without TC :

@bob

I'll test 6% ...

I played a bit with those, but all the results were even worse. Perhabs you can find a setting which is significantly better ... don't be lazy

Wheelspinpart look here:

http://www.lfsforum.net/showthread.php?p=125021#post125021

Well handling is a bit subjective. Its all about a certain feeling. Everyone has a different one. So who knows how a real XF GT e.g. would handle

I floor my cars often and I often drive corners quick enough to make the ESP cut of all throttle and stabilize the car. My former FWD car had no ESP and understeered in those situations.
I also have to change my tires after just 2 years

Cars are not tuned in any way.

Cars won't react exactly as mine, because they are different. But I feel them much more similar to the road going ones in rFactor.

Objective : it is very difficult to drive quick in a slalom or a lap, without having to counter steer the RWD cars in LFS. Even the low powered XF GT is oversteering a lot.

I totally share the opinion of Niels, who made those "road going" setups by using different tires in front and in the back :

Quote from Niels_at_home :

My opinion on LFS was that there where some big tyre issues from the first demo S1 to S2 alpha. There where some improvements but compared to the size of the problem not much fundamentally changed.

This new patch is again 'some improvement', mostly now that the roadcars have a bit more straight line grip than lateral grip. The grip loss / sudden break away problem is still very much there, just slightly less often as with the slightly longitudinally grippier tyres it takes a bit more power or wild driving to get them to spin. But once they spin.. you spin.. There is still no way you can do a slalom even 'only a bit wild' without having loads of oversteer to catch.

Road tyres are still cooked at 100c too, which seems to indicate their 'peak' of 'good grip' is much smaller than what would seem to be realistic.

At this rate sadly, I don't think LFS will become truly superbly realistic until S6.. I do think its less 'wrong' than ISI and I'm certainly not sure that NKpro is 'better' than the lot. So its 2006 and GPL despite doing far less physics things still does the main things less bad than todays sims.

I do applaud the effort and hope the 'official F1 car' will make the devs a wel deserved load of extra orders and $.

Hi all.

Because there are discussions again and again, I wanted to do some objective examination of the problem I see with LFS tyre physics.

Here we go. I will prove my point. I won't use the XF GTI as some say it has not enough torque. I think it has enough, because there is enough wheelspin. (see clutch engaged ... difference of engine revs at 8000 and car speed)

Test paramters :

- I took the FZ50 (street version)
- Default Setup with 25% fuel
- No steering axis assigned to avoid steering during testing
- automatic gearchange activated to garantee the same shifting revs
- I used the car park with attached layout

Test Nr 1

Full throttle from start with TC on :

http://rapidshare.de/files/20129480/FTwithTC.wmv.html

2.83 at checkpoint 1
5.79 at finish line

Test Nr 2

Full throttle from start without TC on :

http://rapidshare.de/files/20129298/FTwithoutTC.wmv.html

2.81 at checkpoint 1
5.72 at finish line

Test Nr 3

Manual start. I tried to do a good start. No rev drop, but less wheelspin.

http://rapidshare.de/files/20129603/manualstart.wmv.html

2.81 at checkpoint 1
5.74 at finish line

____________________________________________

Test 1 and 2 are reproducable. Test 3 isn't, because every manual start is different.
Important is automatic gear change, because different revs at shifting result in different times.

With manual clutch and manual shifting a better time is possible!

Test Nr 4

Old one. XF GTI at acceleration lesson.
I managed a 7.09 with manual clutch and using a keyboard with full throttle.

http://rapidshare.de/files/19158049/709ft.wmv.html

Try to do much better with a good start. I bet a 7.05 is possible, but this isn't a realistic advantage against total full throttle wheelspin at start. It should be about 6.00 possible ...

Try it yourself if you don't believe me or show the videos.

Do a significantly better time with automatic gear change and show it in a video.

Layout attached.

Greetings
RIP

EDIT : 25% fuel used

Last edited by RIP2004, Wed 10 May 2006, 19:56.

Quote from Shotglass :

a) try bobs road going setups (dunno if he has updated them for s/t/u yet) those make the cars as understeery as a normal road car ... its a setup issue not a tyres issue (at least not entirely)
and you can easily kick the tail out in most road cars irl if you overpower the rear wheels
b) the gti doesnt have half enough torque to spin the wheels enough be lose significant amouts of acceleration (but ive told you at least twice already so i guess this atmept will be in vain as well)

a) bobs road going setups didn't change much about oversteer. At least the ones I tried with last version. They just made the suspension soft and ride heigth high. The ones, which really changed the situation were the ones by Nils.
But I'll look for new Setups with version U. I said that it could be the setup ... we'll see. But there is nearly no real car, which behaves like RAC or FZ50. At least no road legal car for usual customers.

b) And I told you at least twice, that there IS a lot of wheelspin. Engine Rev is at 8000 rpm. There is no blue graphic after start, so clutch is fully engaged.
Car speed is from 0 to 50 kph, whereas engine rev is at 8000 all the time. So there is a speed difference between wheels and car of about 50 kph getting lower.

But it is the same with the FZ50. You won't get (really) better results, with less throttle. Switch to automatic gear change, if you want realistic tests. Otherwise you will change situation by other shifting revs.

You see that situation with every car in LFS. I can do dozens of demonstrating videos on that issue. In real life there is a huge difference between a good and a bad starter. You will even notice it in a GTI like car.
In rFactor there is also a huge difference.
I think its also an issue in the problem, that a GTR car like the FZ50 is better off than the formula 1 car ...

I don't understand why a lot of people talk about differences, but can't show them. I bet, you don't even try really ...
Show me a time of GTI a lot better than 7.09.
Or show me huge differences with other cars with more torque. I really want to see that ...

I posted a few weeks ago, but now we have a new version of LFS.

I own both. rFactor and LFS and played both much longer than 1 hour or 1 day or 1 week Offline as well as online.

I still like rFactor at least as much as LFS.

It is kind of annoying, that after months of waiting and another physics update (a direct tyre physics update) there are still major problems (for me) with physics in LFS.

I don't want to talk about how results are produced. LFS has a really great approach by trying to calculate everything. rFactor does some tricks with reading tables. (one big reason for supporting LFS in my oppinion for fans of physics)

But what counts in first place for most players is the result, isn't it? If a simulation simulates something as real as possible, I don't care how it does it. I want to play the result ...

First of the very often described floating feeling of cars.
If I play LFS for a while and switch to rFactor it feels strange for the first few minutes.
BUT it is also the other way around. I even feel more of a sweeping car in LFS, because it doesn't have as many bumps as rFactor I think. You get the impression of flying a few milimeters above the ground. At least for the first few minutes.

But thats not a real point to me.

All racing cars in LFS are really great. And I really think this. All the Formula cars, all the GTR cars. They drive really as I would imagine them to drive. But I didn't drive any of them in real life.
I drove some karts a bit, but it is nowhere near a real car judging by feeling. Perhabs a bit of a small formula car in some way. I would imagine driving formula 1 cars is more similar to carts than to street cars

What I did drive a lot of kilometers are street cars. Mostly FWD, but I drive regulary a RWD car with 180hp. My own car is 150 hp FWD.

And there is the problem. They drive more like rFactor. They feel like a lot more grip. And I am talking about Patch U, which made it a bit better.

The RWD cars still are strange in my oppinion. I don't know if it is a thing about physics, setups or missing electronics. But if a real BMW for example would oversteer that much if you just push it a bit, there would be a lot more accidents.
Millions of unexperienced and partly bad drivers drive RWD cars in real life. And boy, in some real life situations they will floor the throttle. e.g. if they have to join traffic on a highway or taking a 90° corner on their lane.

A lot of them will push the throttle out of a corner if they want to join traffic on the highway.
And a RWD car is very very stable in all of these situations. Deactivate ESP and a modern BMW will still understeer a lot in most situations. You have to be really violent with steering, throttle to really get it to oversteer. At least to get it to oversteer as much as in LFS.

In rFactor you can drive moderate and oversteer won't be a real issue. Like in real life it isn't necessary to know how to countersteer properly.
If you push it, oversteer may happen. If you really push it, oversteer WILL happen.

And there is a weakness of rFactor. You CAN catch slides. But after a certain angle of drifting, physics seem to give up. So I agree about the oversteering problem in rFactor. At some point it gets impossible to catch the drift.
But to that point it is much more drivable and feels much more realistic to me in comparison to real driving.

And I like street cars most like the FZ50, RAC, XF GT or GT Turbo or GTI.

Another thing which is definitly a PHYSICS ISSUE of LFS is wheelspin. In all of the cars its best to start full throttle. You are even able to do the best ranking in Acceleration lesson just with a keyboard. I managed a 7.09 in GTI Acceleration lesson with my keyboard.
Thats a really big issue which should at least in LFS also influence the rest of driving experience on the track.

In all real race series there are huge starter differences. Some cars manage to get several positions ahead. In LFS starts are really boring until the first corner.
All cars start equally because of the arcade signal (in rFactor its more of a simulation and you may react freely to the signal)
And then all cars start as quick as the others. They can just get an advantage by slipstream or another setup. Not by a good driver ...

On the other hand rFactor has a small clutch issue and unrealistic weak brakes on street cars. Both can be modified by yourself in the hdv files. I corrected that myself for me
But I can't correct the "catching slides at high angles" problem. Its really a ISI physics thing, which should be corrected. If you drive well you won't need to get a drift at that angle ... you should react quick enough. So it doesn't matter as much, as constantly countersteering in LFS.

Enough Hopefully someone reads it. Have fun, have to go for now.

Nice to see a lot of these small issues fixed now

Hopefully acceleration won't be an issue anymore after next patch. Have nice holidays ...

Quote from ATC Quicksilver :

You can gain a very slight advantage by taking a smoother start, but not as much as i would like. The FXO or XFR are good cars to test it with because they are over powered fwd cars. If you watch any form of motorsport you see how important it is to get the start right, BTCC highlights this perfectly because the cars are all fwd and pretty powerful.

Still i expect Scawen will be able to fix it in the next physics update so we have perfect tires (lfs already has the most realistic imo)

Enjoy your holiday Scawen and co, thank you for making my favourite game even better

I think a part of it is because of the arcade style signal. You should be a able to start free and react on the signal. Reaction times aren't simulated yet and there can't be false starts ...

But its also because of the physics. There should be a noticable difference of a few meters or perhabs one car length between a good starter and a full throttle starter.
Otherwise testers in the world would all just start all kind of cars with full throttle and take the foot suddenly away from clutch.
The only car I know of to start perfectly like this is the subaru impreza with awd, if you don't like your clutch AWD cars can mostly be started like this ... but the new evo has a special limiter for first gear to make the clutch live longer

Every FWD car or even RWD cars are started by finding a sweet spot lower than the limiter, disengaging the clutch very quick and then regulate throttle a bit to have only little wheelspin.
The results are noticable better than just flooring the throttle to the limiter and disengaging the clutch suddenly.

EDIT:
@Scawen :

I also thought about the cases and I agree mostly.
These are my thoughts:

Case 1: Total wheelspin. The grip level of the tyres while spinning very hard is low enough for the weak GTI engine to hold the wheels spinning up to 40 or 50 kilometers per hour.
A lot of engine torque is just producing tyre smoke by holding the wheels in the bad spinning condition.
Only a part of it uses the low grip available to accelerate the car.

Case 2: Start with slightly increased RPM to make the tyres spin lightly at start. Reason: Engine is at a good rpm for using its torque. Torque of GTI isn't enough to make the wheels spin again after they stopped spinning shortly after start, but ALL of the torque is used to accelerate the car. Traction is perfect. The grip is high enough to bring all of the torque of the engine to the street.

Case 2 should be significantly faster, because all of the engine torque can be used to accelerate the car. Grip level is sufficiant to bring all of the torque to street.
Case 1 just produces tyre smoke ... torque is mostly used to make the wheels spin as fast as possible, NOT to accelerate the car as fast as possible.

Last edited by RIP2004, Sat 29 Apr 2006, 11:00.

Quote from Scawen :

I was thinking about this downstairs, a minute ago.

Even if you can't get a far better time with an analogue clutch, it's not necessarily a sign of a bug.

It's just that the XF GTI power isn't really great, and it just so happens that the limiting factor in both cases, works out about the same. Let me explain :

Case 1 : Total wheelspin - you wheelspin for quite a long time. Limiting factor is the grip of the spinning wheels, engine speed quite constant.

Case 2 : Not wheelspinning - limiting factor is the torque provided by the engine, as it moves through its rev range - it's not enough to break traction without wheelspin, and that means it's not providing the maximum force available at the wheels.

In these two cases, the end result isn't far off, though case 2 is slightly better. I am also interested to know what someone can achieve with a manual clutch - because they will be able to hold the engine nearer to optimum rpm in the first three seconds or so. I was able to get 7:09 still with automatic clutch but without wheelspinning.

NOTE :

In the case of a very powerful car, which has plenty of torque at all rpm in first gear, to reach the limit of grip, you will achieve significantly better times without wheelspinning. I would suggest FZ50 on a short dash, with and without traction control, throttle floored in both cases. Traction control at about 5% or so will win (and same without TC, but with manual clutch, if you can keep it at such an optimum point).

I tested it a minute ago. This time I added a short "track" to the car park. I used the FZ50. It's the same. I tested it with TC on, with TC off and trying it myself.
Only 2 tries of each kind. All automatic gear change. Best result was TC off, full throttle.

You will also notice it when watching usual races on servers. No matter which car, because the GTRs don't do donuts anymore with full throttle (great thing ) since Patch T.
All cars start about equally. If there is an advantage it is because of another gear ratio setup or slipstream.
No car can really get forward while starting. Unlike in real racing series where a good starter may win a few positions ...

Also some people mentioned, that the FZR is faster at the line for the first few moments than the Sauber Formula 1 car, which seems also a bit strange and could be the same problem.

The XF GTI may not have much power, but the rpms stay very high from 0 kph to about 50 or 60 kph until they increase again. So there should be a lot of wheelspin and it should matter for the time anyway. The difference between engine and wheelspeed and speed of car should be around 50 for the first second. So there is enough wheelspin even with the low powered GTI to really matter.

I think this element of tyre physics isn't working correct for whatever reason.
Wouldn't it be possible to program kind of a perfect traction control for testing purposes? Just for a test model or something without to much work? Or something else to test this element of tyre physics?

A good driver should get a noticable advantage while starting against some kind of newbie with full throttle start. In every kind of car.

You can't really experience the lesson "acceleration" which describes exactly what it is about. You are rated "quick" if you ignore the describtion what to learn about acceleration.

Last edited by RIP2004, Fri 28 Apr 2006, 23:34.

Oh I see In germany best is "as".

I tried it and I did immediately a 7.09 with full throttle and keyboard. Just using manual clutch pushing button c.

Here is the video :

http://rapidshare.de/files/19158049/709ft.wmv.html

(click on free to and enter code to download)

Somebody able to do better than 7.09 with proper analog clutch and throttle use?
I think it shouldn't even be rated as "quick" to just floor the throttle with automatic gear change.


If there is a real difference there should be much better times. 6. something with a proper use of clutch and throttle.

Just to make sure there is no bug in it I'd really love to see spinning wheels problem fixed ...
So anyone significantly better times using the better force?

Last edited by RIP2004, Fri 28 Apr 2006, 19:29.

Quote from Scawen :

Well either you are very good, or you didn't unzip the patch properly? Check the file date of "Acceleration - GTI.lsn" - it should be today's date.

Before today, you could get PRO just by flooring it and wheelspinning. Now that will not get you pro, you must use a bit more throttle control.

Strange. I unzipped the patch properly and the date is of today. You need a 7.10 for ace. And 7.8 something for PRO. Right?

If you just floor the throttle (there is no other way just using a keyboard) from the beginning with automatic gear change activated you get a 7.13 and therefore PRO.

If you just floor the throttle from the beginning with manual clutch and manual gear change you get a 7.10 after 2 or 3 tries.
I can do a video of both situations and post it here.

Anybody can confirm 7.13 with automatic gear change and full throttle? Or is it just may PC

I think there is still a problem about tyre physics and spinning wheels. There should be a difference of at least 1-2 seconds between a good start with controlled throttle and full throttle from the beginning.

Good work, but I would like to know what about XF GTI acceleration was too easy? Ace is still possible without a wheel and just with your keyboard
I don't know how to drive, to be below "PRO" ...

Quote from JeffR :

Depends on the tire compound. Some tires lose very little grip when slipping. A bit off topic here, but because of the slipping grip limitations of clutches in most RWD cars, magazine testers just find the sweet spot rpm, drop the clutch and let the tires spin for acceleration measurements. The slipping tires provide more grip than slipping clutches in most cars. I think that stock clutches are designed like this on purpose to keep from breaking transmissions.

That's correct. They find the sweet spot. If it was LFS, they would just floor the throttle and drop the clutch and it would be perfect. You need a certain amount of wheelspin but not that much.
The only car to start perfectly with this method is a AWD car ...

Note also that in race series there is a huge difference between starters. If it was LFS all would start equally with full throttle ...

It is a very old weakness, which is still there ... and most important it is tyre physics, which was one of the main topics of this update ... hope he will improve it again with next update

Last edited by RIP2004, Sun 23 Apr 2006, 00:06.

I totally agree with Niels. Its exactly what he sais. Problems are still there in some way, but its harder to see them. Now you have to push harder to get there ...

The car you choose won't matter.

Just watch the online races and the starts. Everyone with the same setup is exactly as fast as you are. All start with full throttle.
Doesn't matter if it is FZ50, FXO or GTI ...

But try it. I wanna see data ...

jesus christ : learn to read and understand. Then you would notice, that I tested it in the dry ... for real. And not only on the playstation or on pc. The only problem is, that it is bit more expensive for real. But they had to be changed anyway this summer ...

Tell my summer tyres, that I did it in the wet. I have to change them this month. Ever smelled ruber? Would be a hardcore car to make the tyres smoke and smell in the wet

There is no mindtrick.

Two seperate things.

1. Even with low powered cars you will achieve a massive wheelspin in the dry if you rev to the limiter and just take the foot of the clutch. It will last not as long as in a high powered car, but it should be enough for the first few kph and meters.

2. Everyone with every kind of car (low or high power and FWD) can experience the effects in the wet. Because usually noone tries that, but in the wet it happens not only voluntarily ...
It is a bit different and stronger in rain, but you'll see effect. Same in dry but not as easy to see usually ...

Last edited by RIP2004, Fri 21 Apr 2006, 22:45.

I didn't really look at the clutch. But I think I didn't see any blue graphic left. So no clutch. And 8000 revs or so are about 40 or 50 kph, where you have to shift in second to continue acceleration.
Therefore wheels are spinning at lets say 40 kph all the time. So in the beginning there is a difference of about 40 kph, which gets smaller and smaller.
Sure, a proper start is difficult without a real clutch. I just want to see that full throttle isn't the best thing. And I don't want boring starts anymore.

Ever tried a start with these cars in rFactor? There are big differences between people starting there and it is great fun. I want this also in LFS (remove this arcade style signal and give us a free start also plz)

I have to test the thing with the diffs. Could be the reason for the problem with oversteer ...

Last edited by RIP2004, Fri 21 Apr 2006, 21:58.

Maybe with rain. But its also on the dry like this. My car has enough power on the dry (150 bhp on FWD) and it is anything but not a good start with hard spinning wheels. A very short spin is good, but not this bad spinning like with the GTI in LFS.

The problem remains. A full throttle, hard spinning start is the perfect method to get away ... but only in LFS. Even GT4 on the playstation has better physics regarding this issue.

You don't need perf view, to see how hard they are spinning.

Just watch the revs. They are about 8000 from 0 to 40 or 50 kph. This is a HUGE difference between speed and engine revs and therefore the wheels are spinning badly.
And it makes a difference, even in very low powered cars. Ever accelerated a FWD car in rain? See what happens if you have to much throttle ... you will move hardly ...

about oversteer problem :
As I said it could be the setup. But in rFactor for example it works with every car with the default setup. And I am not the only one which has a problem to use this kind of oversteer. See Tweaker. He described it perfectly. There is often understeer then ...


I am not really sure about the braking but in my first tests there was no real difference between locked wheels and a good braking method. But I will test it again ...

Yeah perhabs the RWD cars should behave like very old cars. But the problems in longitudinal behaviour make the behaviour in general wrong. The great thing about LFS is that all the physics act together. And if anything is wrong it will affect everything ... so I am not sure if it would be easier without that problem. But it would be different.

Quote from AJS :

The FZ5 still doesn´t handle anything like a Porsche/Ferrari ! It drives like a pig. I would say the handling comes close to let´s say a Mercedes CLS 350/500, okay maybe not that bad . A Porsche 911 sticks to the road like glue feels very light weight with direct steering and throttle responses.

and yeah ive driven them IRL

The tires are improved but still ...
you can brake down from 240 kmh to 120 kmh like nothing and pull of the craziest drifts without any effort and lose grip at pretty low speeds. Drifting is even more easy than before the patch ! Try this stuff IRL lol

Same impression here, also it has improved in my oppionion.
See my thread about wrong longitudinal behaviour of the tyres ...