Quote from Crashgate3 :

I know what you mean - to me, this is a stock car:

To me, that is a Sprint car.

Touring car is what I call racing with a sedan or coupe type car that has been modified to some extent for racing.

I leave "stock" car to mostly oval racing done here in the US and to some select club racing classes like the SCCA "Show Room Stock" class (those cars are street cars with roll cages and not much more).

To the OP, like said above, LOTA is probalby your best bet right now for a US based series. There are some very fine series run on weekend evenings in Europe that fit pretty nicely into the weekend schedule here as long as you are willing to get up pretty early in the morning.

Quote from Ball Bearing Turbo :

I assume your Miata has an open diff?

It was optional, but I think most did come with the LSD.

Quote from w126 :

Rather then looks, my opinion is more a result of reckoning that the seat does not usually move relative to wheel and pedal base in a real car when cornering, accelerating or braking. On the other hand, finding a car that actually does that (seat moves; not that its constructor wanted it) may be easier near me.

I am looking forward to trying any motion simulator, although getting access to only SimConMOTION seems most likely here. Not sure if it would be any indication of the level of experience provided by the more expensive systems.

Of course the seat doesn't move in relation to the wheel or pedals... but YOU do. Just a small amount of movement of the seat will simulate the feeling of your body movement on g loads. The wheel and pedals don't have to move with this to make it effective. Remeber, you body isn't moving due to g loads because there isn't any in a sim. The seat moving will give you the impression of the g loads.

I personally think that a small seat shaker with maybe a little bit of wiggle to it would be enough to really enhance most home sim situations. Something with maybe a 5° of tilt and an 3 cm of motion would be enough.

I have thought of this before too. One of my problems is that I can't practice enough. I can't tweak my sets to the n'th degree for each track, I just don't have the time.

It would be fun to have a league where you are restricted to testing for only an hour or two for every race. That way, you have to be very diligent about your testing and try and get the most out of it. Then, come race time, it is a bit more evened out. Of course, the best drivers will still win, I would still be mid-pack. But I think it adds another dimension to the game.

However, you would have to have a system that basically policed you when you were not racing online. Of course, LFS checks into the master server every time you start up to verify your license. I am sure a system could be put into place to monitor this. However, it would be easy to get around in a number of ways, so cheaters could still get away with it.

So, the closest thing I have seen so far is what we are doing in the LOTA mini-series we are running right now. There are 6 possible tracks to use and the track is picked randomly just prior to the race. Then we practice for 25 minutes, qualify, then race. If you have tons of time, you could develop perfect sets for all the tracks, but most people are not doing that. It is more fun to "run what you 'brung' " so to speak.

Quote from Damo74 :

I have a AMD 2800+, 1GB RAM, Radeon 9800 Pro with 256mb and I get 50-60fps regularly. On fuller grids, I can get about 30-40fps. I think there might be something else at play with your system.

Plus 20fps is easily driveable, you dont need over 40fps to play, thats just being stupid. The human eye only detects so much....

My definition of driveable is different than yours. I am not willing to live with stuttering, skipping cars and stop-go motion. It is too easy to miss turn in points, braking points, and where other cars around you are.

Yes, you can play the game with less than 40fps. Will you be as competitive as somebody with the same skills who is getting 60fps? No you won't.

I saw a big improvement in my lap times after I got a better video card. My frame rate was more consistent and everything was much more smooth. It leads to smoother driving. And no, I didn't have better resolution set and I wasn't using more eye candy, I just got more frames. (this is only true up until a point. Anything much past 60fps isn't doing you much, if any, good)

Movies run at 24fps. But, they are shot on film and if you freeze frame you will see motion blur. You won't see that with computer graphics. That is why you need a higher frame rate for computer graphics to make things look smooth.

I can visually tell the difference between 40fps and 60fps. It is quite noticeable. If you can't see that, don't blame it on me.

Quote from Ball Bearing Turbo :

But Eric, that's like telling Tristan that he hasn't discovered his mind because he thinks oval racing is boring. Doesn't work.

I don't find any of the tracks boring, I think they're all quite engaging actually - but I can't belittle someone because they think a track is boring.

That wasn't really the point Jeff. If you (the generic "you" meaning whomever is reading this) find oval racing boring, well then don't do it. If you find all the content in LFS boring, and complain that you just can't play it anymore until new content comes out, then I would argue that you are just skimming the surface. It kind of goes back to what mrogers said earlier, but I wouldn't have used those words.

There is so much more to LFS and racing than a new track or even a new car. If you are not entertained by the current stuff, then you will only be entertained for a few weeks or a month if and when they do add new content. It is a perception problem and a desire for others to entertain you rather than you making the most of something and entertaining yourself.

New content is always welcome. I would like to see some more stuff myself. However, good racing is good racing. I can always shave a few tenths off of laps. I can always work on really understanding setup changes to make me a better racer. If you think you have peaked, well, that is the time to dig deeper and fight to improve. It isn't the time to start complaining about needing a new track.

All of this is just my opinion. Nothing more.

Quote from maczo :

These are two completely different things. I'm not even close to doing a WR on AS National in any car, but I don't ever ever race it unless it's in a league event, which then I just have to. It's THAT boring

On a sidenote - funny, how Aston got me bored a lot faster than South City, which we've had for a lot longer and which I could still drive every day. Says something about track attractiveness

If you are bored, then you are not putting enough into it. There are so many more facets of racing than just lapping or even pickup races online. Skinning, setups, understanding the physics, what exactly does 50 Knm/s really mean... etc. Plenty of stuff to do. Organize a league, put a team together for endurance racing... man the list just goes on.

The point is, if you are bored, then I will tell you the same thing I tell my kids: We are not responsible for entertaining you. Quit whining and go engage your mind. You just might find out that you have one and it can be very entertaining to play with.

Quote from KartRacer :

... I just hope they continue doing what they have been, because if they do, this sim is only going to get consistently and astonishingly better as time goes on.

Well said!
Man, you don't post often, but I may have to go back and read all your posts if they are as good as this.

Quote from Shotglass :

hehe they are a tad hard to read
maybe 2 3d surface graphs of lateral and longitudinal forces over both angle and ratio would be easier to understand

You do have to study those charts a bit... they do look like brain scans

One thing that comes to mind for me looking at the circle charts is tire deformation. Obviously, when in a corner, the slip angle is high. The sidewall is going to be flexed. But when you add power to the wheel, your slip ratio goes up, but wouldn't your slip angle go down slightly? Or at least change some?

The reason I ask is that looking at the charts, specifically the slip ratio chart and the 8° slip angle (red) it seems that it is possible that adding power would force the tire to a different shape and reduce slip angle. The tire can only flex and twist so much. The longitudinal stress of applying power has got to have some effect there. I kind of look at it from an aerodynamics standpoint where you have relative wind. This is the resultant vector airflow over an airfoil after combining wind, direction the aircraft is moving, prop/rotor wash, etc.

This is also where some robotic (AI driver) testing would be nice. Having something that could drive the same course in the exact same way multiple times would help with data analysis I think.

It also seems to me that if you used look-up tables for tire data, the results we are seeing in those charts would be more predictable and homogeneous than what it seems to be... but I might be way off the mark with that thought.

Quote from tristancliffe :

What is wrong? GTR, GTL, rFactor Mods, GTR2, Race.... The list of mediocre sims that have had 'real driver input' goes on and on. Either the drivers don't know how cars work, or the people that make the games listen politely, then ignore them.

lol, probably the latter.
But seriously, a lot of drivers have no experience with sims. They have a hard time translating the real world g forces and speeds to a strictly visual experience like it is in the sim. Their feedback is not something I would rely on heavily if I were trying to build a sim.

20-30fps is low for LFS.
You really need 40+ to be remotely drivable.

If your "original" video card is the one built onto the mother board, then it is a large part of what is holding you back. It will most likely also use your RAM for video memory, so it is a double whack.

Get a newer more capable video card. I am sure you can find something for less than $100 that will work.

Pressure differences between hot and cold on DOT street tires when used on a race track can be as much as 10 PSI. I typically see 7-8psi on my car (mostly on the front left which is the tire getting worked the hardest).

I would call that pretty significant. I would suspect that full race tires are at least if not more sensitive than my street tires.

If we are setting hot pressures, then LFS has the pressures really, really low compared to the real world. Typical hot pressures are going to be in the mid 40psi range for most street tires.

I did check out the F9 views a bit more last night. The surface view does show a rapid gain and loss of temperature, just like it should, at least on fresh tires. The inner rubber temp just kept getting hotter and hotter and the relationship between the surface and the inner temperature seemed odd at times. I just can't exactly explain why though.

I did notice too that tire deformation didn't seem to change as the tires got hotter. You would think that because the tires are getting hotter, the pressure would be going up, and the deformation would be less. It is probable that the difference is just to small for me to notice though.

Quote from Gnomie :

Hang on.. a material's heat conductivity is irrespective of the direction of heat flow..

Or were you talking about something else?

No, that is what we are talking about. It shouldn't be that way because of your point.

Quote from Ball Bearing Turbo :

Agreed; and not enough in the opposite direction - ie heat is not taken away fast enough from the internal rubber.



Really? After a corner it only takes a second or two before the surface temp is down around / below the internal rubber temp. You think it should be even faster?

Hmm, maybe I will look at that closer. I could be wrong there. I don't look at surface temps all that much.

Quote from tristancliffe :

I don't really know.

We asked Avon what a recommended hot tyre pressure should be, as was told 20psi. So we just set our cold pressures to reach that after a run (which works out at about 15psi on the more loaded side and 16psi on the less loaded side, depending on the track of course).

Measuring temps across the tyre generally seems to show reasonably even temps, with a slight peak in the middle - perhaps we need to lower the hot temps, but Avon said that was normal and okay when we showed them our data.

But we haven't used pressures to control tyre temps. Or camber yet. If our tyres get too hot we'll cope some other way - perhaps spring rates, or perhaps saving up and buying a slightly harder compound of tyre.

You need to ask a professional racer/tyre person this sort of thing, as it's out of the depth of most club racers (ourselves included) due to lack of track time.

Good answer. I guess the important thing here is that each type of tire has an optimum hot pressure that they should run at. In the LFS case, it is the lowest pressure possible where your tires don't overheat. I think that is a bit odd.

Secondly, you said it yourself. You use 15psi cold on the loaded side and 16psi cold on the less loaded side. So, you are not using pressure to control temperature, but are using temperature to control the hot pressure. This is again different than in LFS. In LFS, we use pressure to control temp and to some degree the other settings you talk about, but not so much.

Thanks!

Last edited by Hallen, Thu 8 Nov 2007, 21:34.

Quote from AndroidXP :

Just to make sure, when you refer to "surface temps" in LFS, you mean the F9 view with shift+ctrl pressed, do you? If not, you're not looking at the surface temps but at the rubber inner temperature.

Yes, I mean the ctrl+shift F9 temps, but also to a degree the internal rubber temps. Heat transfer seems to happen too easily to the internal rubber, and the surface temps don't cool as quickly as they should. The interanl temps get hot to quickly because of the fast heat transfer, but don't seem to cool as quickly as they should either.

I think the other area of concentration should be tire temperatures and pressures. This might be a side effect of the load sensitivity issues or other issues, it is hard to say.

But, what do we do in LFS if you need to decrease tire temps? You raise the pressure which seems to be opposite of what you would do in RL (Tristian... is that generally true?). You also reduce camber some.

IRL, lower cold pressures allow more pressure build up in the tires, and the tires stay more cool throughout a stint. In LFS, this is not true.

Also, tire heat seems to build up and not dissipate quickly enough. I am not really talking about internal temperatures, but the surface temps. Watching an F1 race, they had a new graphic this year. The graphic showed tire temps. Going through a long corner, you would see the temps rise quickly. Then, on the subsequent straight, the tires would cool quickly. This does not happen in LFS.

These problems might also have an effect on the longitudinal grip problems that we see.

These are just my thoughts, there are no scientific studies that I have done.

Software development on products for sale is much, much different than for some personal home project... even if the intent is to eventually sell it. Testing, code reviews, code design for maintainability, etc, all plays a roll in how long something takes.

Software development is tricky stuff. Somethings that seem incredibly complex to us, might be a very straight forward mathematical problem to a computer. Other things, which seem straight forward and simple to humans, are virtually impossible to do with a computer. It all just depends.

mrodgers, sometimes you are correct, editing and updating legacy code can take longer to do at times. But this is only if that code is part of supporting classes and data structures that are used in other parts of the program that are not being changed. Then you have to work around existing structures to get done what you need to do all the while trying not to break the other code. Sometimes it is easier to just write stuff from scratch. However, most of the time, it is the ground work that takes the time. The final implementation is fairly straight forward.

Something like getting the AI to be intelligent can be more difficult than what we would think it should be. Software does not make rational decisions and it cannot change once compiled. To make something react in a rational manner in software is quite a trick. I will be very interested to see what Scawen comes up with. Even with the restricted "rules" inside the sim, it will still be a big challenge.

Don't think to yourself that any of this is easy. People have been trying to create tire simulators for years and have only gotten them to partially work. The big question becomes "how do you test it?". There is some math that will help, but in the end, it all comes down to feel. Does it feel right? Does it behave correctly in all situations? How do you quantify that feedback and how do you turn it into verifiable computer code? Not easy stuff to do.

When I ask for a time estimate from my Engineers, I get a guess. "It will take what it takes" is the answer I get most of the time. This is because that software development can still be more of an art form than a science at times.

I think if you go back and watch all the ALMS races this year, you will see a perfect example of cars, the Audi R10 and the Porsche Spyder, that are very different yet run nearly the same lap times. One is an LMP1 and is larger, longer wheel base, with gobs more power... but it is heavier. The LMP2 Spyder is lighter, smaller and much more nimble.
On the tighter tracks, the Spyder was the clearly faster car. On long tracks, the R10 was clearly faster. But on the in-between tracks, it was a heck of a battle. If the R10 ever got in front, it was very tough for the Spyder to pass because the R10 would just gap them on the straights.
But if the Spyder could get by in the corners, and they had enough time before a straight, they would pull away.
On tighter tracks, the R10 would use traffic to their advantage because of their huge torque and make quick work of slower cars. The Spyder would lose momentum getting around traffic allowing the R10 to either catch up or build a gap.

It all made for some exciting racing.

The point is, even if all the GTR cars are made so that we can run identical lap times in hot laps, racing against each other will still be a challenge. For example, the XRR has a bit more top speed down the straights, but it is almost useless because the FXR will get a much, much better jump exiting the last corner. They can get so good of a jump, that the XRR can't catch up even along the longest straights. To get by, you have to race. Find the weakness in the other driver or other car, and fight your way past. That is as it should be.
So, don't worry too much about equal lap times. I think they should be as close as is feasibly possible. But, because of the different nature of each car model (thank you Scavier), there will still be advantages and disadvantages to each car. This is as it should be because they are different cars. It ain't spec racing here.

Quote from mrodgers :

Priceless....




The only thing that doesn't do it for me with LFS is in the middle of the corners. I don't have experience behind the wheel of a race car. But I've seen plenty of onboard footage. If you watch online footage of real racing, you hear the drivers brake, turn in, then ease around or go part throttle around the apex very often. I don't know if it's the physics, the way corners are laid out, or what in LFS, but we have none of the coasting or part throttle around corners. LFS corners are taken as brake, turn-in, full throttle, exit. There is no middle where you have to modulate the throttle mid-corner. I'm strictly thinking in the tin-top sense though as I'm not fond of the open wheelers.

Tristan or anyone else who's had track time or race car time? What are your thoughts to that having driven race cars? Does that have to do with LFS's track corners, the physics, the tires, what? A common thought is probably the 'fear factor', but I really don't think that is it. The 'fear factor' or 'seat of the pants feel' may have something to do with it, but I am thinking that is not entirely the reason.

The reason it is done in the real world is to stabilize the rear of the car and to maintain speed through a corner (coming from a guy with a few hundred track day laps, so FWIW). You want to keep the tires as close to the edge as possible and if you don't apply power through a corner, you will slow down. But, stabilizing the rear via weight transfer is one of the bigger reasons for doing it. If you ever do a track day with an instructor, they will harp on you to keep your foot on the gas. It helps to keep you pointed in the right direction.
I think inside LFS, or any Sim, people do basically what Tristian says. They can practice so much on completely predictable surfaces, that they can get it perfect. Also, because of the setup options we have, it makes it possible to aggressively trail brake into corners where it just wouldn't work as well in the real world.
There are corners in LFS where throttle maintenance is needed. Turn 5 on KY National is a good example. If you are in the LX6 for example, you can't just mash the gas once you turn in. You let some speed bleed off while maintaining a bit of throttle, and then your roll the throttle back in again at the right time.
But, mostly it is just the ammount of practice and the aliens. I have to coast a bit on some corners and use maintenance throttle. I can't just trail brake, and then floor it like some can.

Quote from jtw62074 :

Nice videos and site, Hallen.

A friend of mine ran a couple of Donkervoort series for a few years (open top Lotus 7 types) and filmed several of his races and so on. It took awhile for him to figure out how to get rid of the wind noise and let the engine sound come through more. Eventually, he stuck the microphone under the dashboard on the passenger side, up towards the firewall. This is the result:

http://youtube.com/watch?v=Dp7g1NAMNxE

I went for a couple of rides in this car, and the video sounds very much like it does in reality, although I couldn't hear the turbo like you can in the video. (The car pictured in the video is wrong, by the way, although the driver's name is correct. Wolfgang wasn't actually driving his own car here, but my friend's. We don't know how they got this video and were surprised to find it online )

Anyway, regarding mic placement, maybe you might want to try the same thing? It sounds rather windy, although the video quality is very nice!

Nice vid too, it is unfortunate that Youtube compression munches it so bad. That is why I got my own domain so I could host better videos.
I just use a Nikon digital camera for my videos. It is light weight, simple and mostly, it is cheap.
It does do 640x480 video at 30 frames per second, so you can't complain about that. The mic is on the camera and there is no way to put an external mic on it. I am going to try and rig up a muffler on the mic to try and reduce some of the wind noise. Unfortunately, that is not going to help you hear the car much. It is pretty quiet the way it is. It is just a street car and my daily driver so straight pipes are not an option.

Quote from danowat :

Not so much bumps in tracks, but the way the cars react, they just seem too smooth, maybe it is the tracks, maybe its the smoothness of the cars, maybe its a bit of both, but LFS needs some more "rawness"

I think the cars react perfectly. If you really had your butt in the car instead of sitting on your stable apartment floor, you would then notice all the bumps.

Until the point where all of us can afford some kind of motion seat, you just won't feel it and will think the cars aren't moving enough.

The only fix for this is to exaggerate the bumps, like rFactor does, and make the sim more unrealistic.

Personally, I think that if you really use your eyes and really immerse yourself you will see the bumps, and you will almost feel them. BBT said it, he cringes waiting for the car to hit after getting air. That is because the reaction of the car is believable which makes you anticipate actual physical impact... which of course never comes because you are not physically there.

Are we talking about bumps in the track or are we talking about that annoying thing that rFactor does where the whole dash bucks up in the air when you hit a bump? I mean, it looks like the whole car is made up of separate parts and the steering rack is made of rubber. It is silly. Real cars don't look like that when they go over bumps.

Your eyes don't work like that either. If you have your eye on a spot in front of you, they will track that spot no matter what bangs and vibrations are happening. Your eyes do not work like a helmet cam.

Until you get a full motion setup, it will just look silly if you try and do things like rFactor does. I have to turn all that stuff off to drive rFactor. It is too distracting otherwise.

I don't think that the tracks in LFS are too smooth. Race tracks in general are smooth, at least ones that get any kind of regular maintenance. They are much, much smoother than real roads. I think South City has plenty of bumps in it they way it is. Aston has bumps. You can feel them and they will upset the car if you hit them wrong. It makes braking difficult in certain places.

I guess I just don't see the problem.

Quote from Ball Bearing Turbo :

You should post more often Eric; it's always good. Some in car vids of that BMW would be sublime, hint hint

It ain't much, but it is fun for me
High Res videos are linked and embeded on the blog.
http://www.griplimit.net

Quote from benoityip :

I owe LFS and rfactor and GTR2, and I am play a lot of rfactor everyday.

I like the tyres and differential modelling in LFS, it is better than rfactor I think, but I also like the ability to set Engine RPM and weight distribution in rfactor

I have downloaded many mods, some mods are crap, but some mod has very good physics, even better than LFS default cars.

If you guys own GTR2 as well, the GTR2 cars have excellent handling..

I like LFS as well, but the cars are too frictious, feel like an arcade drift game

The same goes for rfactor, the demo cars are too frictious, feel like an arcade drift game, especially in suspension areas

but with mods in rfactor, that changes the whole story.. If LFS allow modders to mod real life cars, I am sure people will find LFS even more stunning as well.. It is just the parameters feeding into engine are not correct

I have spent quite a bit of time trying to get rFactor to work. It doesn't matter if it is a fictitious car or a "real" modded in car, they all feel vaguely the same. Rotate about the middle, the same unpredictable tire behaviour, the same unpredictable braking, and Real-feel, although an improvement over stock, is still lacking compared to LFS. If you make a car setup well enough that it will actually turn-in on any corner in rFactor, it is so unrealisticly tail happy other places that it is just funny. It is just your opinion, as this is just my opinion, but calling LFS cars "arcade drift game" is just showing that you either haven't spent the time to learn how to properly setup a car, or you just have no clue.

LFS allows for an extremely wide range of settings changes (probably too wide), and that throws a lot of people off. You just don't crank things up all the way like you do in rFactor to get the results you want. It takes small tweaks and a real understanding of car setups to make a car work well.

I have spent many hours on a real track in a real car driving at the limit... and sometimes slightly past the limit. The comparison is extremely difficult to make between real world and the sim world. But, like Tristian, I can say with a lot of confidence that LFS comes much, much closer than rFactor.

Damn, I swore I would not ever post in this thread again... and there I go.

Yeah, I left the private guestbook entry. It worked fine for me with IE.

Thanks for the answers Bob. The entry screen is fine in the units it is for now. Not a big deal at all.