So how do ' bone stock' well driven laps compare to real Nurburgring laptimes?
Thats probably more effective in attracting 15y/o girls than it changes the aero. I have a wind tunnel measurment of a cars front end lift in normal shape and with a splitter type thing.
At 70mph the difference was 4.5 kilo. Sure you might have a super splitter that removes 9 kilo of lift, but thats neither noticable nor effective !
Its the tough thing about cultures and country habits where its easy to think yours is superior. To a guy from India the sight of a western dude eating a burger might bring up the same emotions as some of those in this thread against chinese animal cruelty.
195 / 50 / R15, peak slipangle ~ 11 degrees, stiffness 1400N/deg @ 6000N load
325 / 30 / ZR19, peak slipangle ~ 6 degrees, stiffness 3000N/deg @ 6000N load.
Glass is right!
325 / 30 / ZR19, peak slipangle ~ 6 degrees, stiffness 3000N/deg @ 6000N load.
Glass is right!
I still think the only thing you're going to achieve, regardless of your best attempts, is an internet brawl on what IS realistic and what isn't. That is almost inevitable as there is very limited real data available, and at least half of this 'real data' about tires has turned out to be rather wrong.
We have all the ingredients for a brawl here..
That is almost inevitable as there is very limited real data available, and at least half of this 'real data' about tires has turned out to be rather wrong.We have all the ingredients for a brawl here..
You can have all the tire flex in the world running at 100000000000000ghz but that won't compensate for entering the wrong values for peak slip angle etc..
Often MORE numbers just means more things to get wrong!
Often MORE numbers just means more things to get wrong!
Umm the idea is to compare the Real nurburgring with a real car to a simulation of that car and track. Sure there is no hand movement in rFactor, nor do you see those hands when you're actually racing. Its just a 'dummy' so you see a driver in the car..
I dunno, I think its pretty impressive that sometimes the sim is exactly at the same place, revs, speed as the video, for example the first 1.5 minute and the section after Hohe Acht until Schwalbenschwanz.
I dunno, I think its pretty impressive that sometimes the sim is exactly at the same place, revs, speed as the video, for example the first 1.5 minute and the section after Hohe Acht until Schwalbenschwanz.
I bet there are quite a few rfactor mods where laptimes are sort of realistic. But tires loosing 20% grip purely from going 300km/h, having peak slip angles 3x greater than realistic and grip curves that are from a different planet... THe actual driving experience is not realistic at all.
If I may brag a bit about my Z06. I have real tire data which is detailed enough for not only peak slip angle and stiffness, but also load sensitivity. We also know the weight, weight distribution and have a good guess on how height the center of gravity is. Then we have suspension geometry from a c5 corvette; which is roughly the same, giving us usable roll center locations and migrations, anti dive and squat etc. We have a detailed torque curve and know drivetrain losses because the Yanks love to dyno their cars. Coupled to gear ratios and a known diff lock, we know quite a few things. Aero lift is known as well, as is drag.
We don't know exact springrates (or rather wheelrates) though again we have some C5 numbers which might be somewhat close. We also don't know the anti roll rates, but again with plenty of videos available you can visually decide on something that is 'close' in body roll.
The chassis balance, TLLTD (total lateral load transfer distribution) is basically the front vs rear chassis roll stiffness, so each ends combination of roll center height, wheelrate and anti roll. Typical figures are in the 60% range for sporty behaviour, but in case of the corvette, the extra grippy rear tires could shave a few % off without making the ride all too hairy or dangerous.
Less known is tire traction; but you could say that modern ABS systems get pretty much all of the available grip out of the tire. With a reasonable brake bias of ~75% (thats only a few % in front of 'critical!!) you can decide on the longitudinal tire grip. Of course, this should also be enough for the car to do its 0..60 times.
Now, if the physics engine is good, first it should allow me to put in all this real data. Secondly the results of this data should match published real car data.
In case of the Corvette, just creating a car like I mentioned above, will pull about 1.04G on the skidpan. No tweaking of grip, just using the tire data, suspension data and a believable 58% TLLTD. Thats just impressive because the real car measured at 1.04 by Chevy themselves, and a few reviews got 1.02 / 1.03. Brake performance is within a yard, and 0..150mph is within a few tenths.
I think such an approach not only proves that the physics engine is pretty good, it also shows that this realistic aproach is the only way to go. Sadly the tire data I have for the Z06 isn't available for many tires at all, so sooner or later you're going to have to rely on common sense and clever interpretation of 'other data' to get a car going.. And of course the physics engine isn't perfect and things like combined tire forces are mainly down to the physics engine. So even in this case, while the numbers are truly realistic and the engine is good, the actual driving experience might still be somewhat off due to imperfections in force combining and perhaps other areas...
If I may brag a bit about my Z06. I have real tire data which is detailed enough for not only peak slip angle and stiffness, but also load sensitivity. We also know the weight, weight distribution and have a good guess on how height the center of gravity is. Then we have suspension geometry from a c5 corvette; which is roughly the same, giving us usable roll center locations and migrations, anti dive and squat etc. We have a detailed torque curve and know drivetrain losses because the Yanks love to dyno their cars. Coupled to gear ratios and a known diff lock, we know quite a few things. Aero lift is known as well, as is drag.
We don't know exact springrates (or rather wheelrates) though again we have some C5 numbers which might be somewhat close. We also don't know the anti roll rates, but again with plenty of videos available you can visually decide on something that is 'close' in body roll.
The chassis balance, TLLTD (total lateral load transfer distribution) is basically the front vs rear chassis roll stiffness, so each ends combination of roll center height, wheelrate and anti roll. Typical figures are in the 60% range for sporty behaviour, but in case of the corvette, the extra grippy rear tires could shave a few % off without making the ride all too hairy or dangerous.
Less known is tire traction; but you could say that modern ABS systems get pretty much all of the available grip out of the tire. With a reasonable brake bias of ~75% (thats only a few % in front of 'critical!!) you can decide on the longitudinal tire grip. Of course, this should also be enough for the car to do its 0..60 times.
Now, if the physics engine is good, first it should allow me to put in all this real data. Secondly the results of this data should match published real car data.
In case of the Corvette, just creating a car like I mentioned above, will pull about 1.04G on the skidpan. No tweaking of grip, just using the tire data, suspension data and a believable 58% TLLTD. Thats just impressive because the real car measured at 1.04 by Chevy themselves, and a few reviews got 1.02 / 1.03. Brake performance is within a yard, and 0..150mph is within a few tenths.
I think such an approach not only proves that the physics engine is pretty good, it also shows that this realistic aproach is the only way to go. Sadly the tire data I have for the Z06 isn't available for many tires at all, so sooner or later you're going to have to rely on common sense and clever interpretation of 'other data' to get a car going.. And of course the physics engine isn't perfect and things like combined tire forces are mainly down to the physics engine. So even in this case, while the numbers are truly realistic and the engine is good, the actual driving experience might still be somewhat off due to imperfections in force combining and perhaps other areas...
Even when laptimes match, there are near infinite wrong ways to achieve this! You also have the complexity that you can't judge a physics engine separate from how well optimzed the numbers that go into it are.
Ultimatly you can't really look at the total car. Sure laptimes could be right, even G forces could be right, but you could still achieve this by having the wrong tire loadsensitivity and wrong aero to compensate.
I think you'd have to break it down more and draw tire charts from each sim, from which you can derive a few key things such as loadsensitivity, stiffness etc.
Chassis wise, you can calculate the ride frequency and TLLTD and see if it makes sense, and the suspensions can be analyzed for roll center position, camber change, bump steer, anti dive etc..
Then of course, which is better? Despite all the hard work above It'll probably still be a lot of forum ramblings..
Ultimatly you can't really look at the total car. Sure laptimes could be right, even G forces could be right, but you could still achieve this by having the wrong tire loadsensitivity and wrong aero to compensate.
I think you'd have to break it down more and draw tire charts from each sim, from which you can derive a few key things such as loadsensitivity, stiffness etc.
Chassis wise, you can calculate the ride frequency and TLLTD and see if it makes sense, and the suspensions can be analyzed for roll center position, camber change, bump steer, anti dive etc..
Then of course, which is better? Despite all the hard work above It'll probably still be a lot of forum ramblings..
http://www.youtube.com/watch?v=FoB9EzL-KCM
real vs rfactor similar cams. That makes it a better base for comparison! Excuse the low framerate and sound that beats the laptime by about 5 seconds.. :S
No tricks or syncing though, just started the video and replay at the same time and then captured the screen at a crappy framerate! I also tried to use Ati control center to change the saturation of rFactor but that didn't seem to work.
real vs rfactor similar cams. That makes it a better base for comparison! Excuse the low framerate and sound that beats the laptime by about 5 seconds.. :S
No tricks or syncing though, just started the video and replay at the same time and then captured the screen at a crappy framerate! I also tried to use Ati control center to change the saturation of rFactor but that didn't seem to work.
Last edited by Niels Heusinkveld, .
Forget Fifth gear, I want Tiff Gear!
http://www.youtube.com/watch?v=FoB9EzL-KCM
If that was true, I should be able to set a 7:26 in a real ZR1 at the ring; which I doubt I'd do without taking some very advanced chemicals that reduce the 'fear' part of my brain into pulp..
But of course, I'd know the shift points, brake points, lines, and this is just a 'fairly' good 3d interpretation of the Ring, really not that good.
The part where simracing can teach, but doesn't have to, is in the driving style. For some reason in a sim people tend to be much more rude and abrupt with the inputs than you'd do in a real car. Perhaps its the G forces lacking in simracing but its not often true that she simracing driving style looks a lot like a real one..
If that was true, I should be able to set a 7:26 in a real ZR1 at the ring; which I doubt I'd do without taking some very advanced chemicals that reduce the 'fear' part of my brain into pulp..
But of course, I'd know the shift points, brake points, lines, and this is just a 'fairly' good 3d interpretation of the Ring, really not that good.
The part where simracing can teach, but doesn't have to, is in the driving style. For some reason in a sim people tend to be much more rude and abrupt with the inputs than you'd do in a real car. Perhaps its the G forces lacking in simracing but its not often true that she simracing driving style looks a lot like a real one..
Cliffe, are you trying to aggrevate (sp) me so I'll eventually end up making your car for free? :P
In 'tight' racing situations where you're using a few degs or a few % slip, rFactor probably combines the forces as wrong or less wrong than LFS you know :P
In 'tight' racing situations where you're using a few degs or a few % slip, rFactor probably combines the forces as wrong or less wrong than LFS you know :P
Usually though when you can feel the bumps in rFactor, it is because they are horribly overdone. A great part in making rFactor better is getting rid of most of the silly sine wave bump patterns!
Reviewd by SimHQ as well, see my sig
That looks very floaty and detached. Sure you can't take hairpins at 120mph but it doesn't seem to be very realistic from a handling pov..
what do you have the logitech software effects strength at? And what percentage of FFB you set in LFS? Keep the first at or below 100 and in LFS, it depends, but probably never more than 25% or you'll be overloading the motors.
Run 100% on both and overheating can be an issue, which will reduce FFB.
There is also good news, the faster the momo wears out, the sooner you can get a better wheel.. :P
Run 100% on both and overheating can be an issue, which will reduce FFB.
There is also good news, the faster the momo wears out, the sooner you can get a better wheel.. :P
how much RAM does lfs actually use? play it in a window and do control/alt/del, see in the taskmanager.. there is no need for 'more' memory than ' enough memory'.
I bet just a cheap 2nd hand 3d card will make LFS 'ok' on your pc. Ebay?
I bet just a cheap 2nd hand 3d card will make LFS 'ok' on your pc. Ebay?
The cheapest agp (i assume) second hand video card will be an improvement, like even a geforce 4 TI or ati 9600pro, they can't go for more than 20 euro second hand. That should make things nice and playable.
What happens here is that your 'parental home' life slowly fades as more and more old friends move out to Unis all over the country, or move for work, relationships etc.
Often, your old home is a sinking social ship. The only exceptions I've seen are people who are born and will probably die in the same town; which is all fine if you choose so, but one could argue that a more interesting life can be had by broadening ones horizons. Uni in a different town is an excellent way to grow up and learn to deal with the ups and downs of 'adult' (yeah right!) life
There is no real campus going on here, most students live in houses or flats, and when you go online to find a room, you'll be invited over and if it 'clicks' with the housemates, you've got the room.
Often, your old home is a sinking social ship. The only exceptions I've seen are people who are born and will probably die in the same town; which is all fine if you choose so, but one could argue that a more interesting life can be had by broadening ones horizons. Uni in a different town is an excellent way to grow up and learn to deal with the ups and downs of 'adult' (yeah right!) life
There is no real campus going on here, most students live in houses or flats, and when you go online to find a room, you'll be invited over and if it 'clicks' with the housemates, you've got the room.
Heya, shipping is in an envelope, more would mean a package which is more costly. Of course if you want 10, we could probably make a good deal..
new tire physics, new track, thats all very good news.
it looks a bit rfactor-y and I mean that when people drift most cars, opposite lock seems more risky than it will do good. Might be the age old issue of grip dropping off post peak..
Its the beauty of a sim.. Traction loss has no direct relationship with FFB.. but what happens if the back steps out, the front tires will want to keep ' rolling' .. so you experience force feedback that tries to turn the wheel, keeping the tires pointing ' forward' ..
That is all up to the sim. A proper sim models the suspension geometry and tire self alligning torque, which will result in proper force feedback in all situations, providing you don't set the FFB too high which can cause 'clipping' of the higher forces.
The g27 might give a little bit smoother FFB so you feel small things a bit better but overall, the difference won't be night and day.
The g27 might give a little bit smoother FFB so you feel small things a bit better but overall, the difference won't be night and day.
FGED GREDG RDFGDR GSFDG