Have a bit too much spare time.

[FPVaaron]

I did this a few days after I did the 1/4 times cars 0-100km/h (62.15mph) and 0-160km/h (99.44mph) times with defult setups.




Car 0-100 0-160



Xf gti 8.23, 21.40

Xr gt 7.89, 20.80

Xr gtt 5.43, 12.17

Rb4 gt 5.21, 12.59

Fxo 6.06, 12.71

Lx4 4.85, 11.12

Lx6 4.35, 8.99

Mrt5 4.99, 16.38

Uf1000 10.74, N.A

Ra 4.59, 9.23

Fz5 4.41, 9.31

Formula xr 3.89, 8.19

Xf GTR 4.99, 9.89

UF GTR 4.85, 9.91

Fv8 3.65, 5.72

FXo Gtr 2.87, 6.27

Xr gtr 4.05, 7.22

Fz5 gtr 3.27, 6.33

[FPVaaron]

Wouldn't let me space them out so it's a bit hard to read.

[AndroidXP]

Have a bit too much spear time.Oh no! Please don't stab me :schwitz:

Hmm, looking at those times and comparing them to real ones, we actually have a pretty powerful bunch of cars at our hands. Yet still many people have the need for more speed (arrgh). Quite astonishing what the missing G forces can do to a reputation of a car.

I love the NA by the UF1000 Haha

[Shotglass]

a assume they are all done without lifting durings shifts and with getting the intake pressure up as high as possible before shifting into 1st ?

[CrazyICE]

nice "stats" again :)

[Scawen]

Wouldn't let me space them out so it's a bit hard to read.If you use the "CODE" tags then you can space things out like in a text file. In fact you can paste it in from a text file as long as you only used spaces, and not tabs.

After pasting it, you can highlight the text and press the button in the editor like this : #

1. abc 123 xyz
2. abcd 999 www

[noemfie]

The FXO GTR stat is very interesting :)

[Lola Popeye]

LOLZ ZOMGWTF! just noticed now that u mention it.....yes very interesting, so r the rest of the GTR's (maybe we have some time dilation on our hands)

[Bob Smith]

LOLZ ZOMGWTF! just noticed now that u mention it.....yes very interesting, so r the rest of the GTR's (maybe we have some time dilation on our hands)
What? The times seem fine to me.

[DodgeRacer]

Watch some touring car races, those things are rockets untill the downforce/drag kick in. Those numbers dont suprise me, some of the road cars do though, seem a bit fast considering the cars hp/weight

[ajp71]

Some very fast times in the road cars, the Mini is at least 5 seconds to quick:scratchch

Think the race cars are more like it though

[96 GTS]

The FXO GTR stat is very interesting :)
If you launch the FXR really hard, it pulls over 1.2gs of longitudinal acceleration until you shift into second. That stat seems correct to me.

[Tege]

Some very fast times in the road cars, the Mini is at least 5 seconds to quick:scratchch

Think the race cars are more like it though
Actually RA is about right... (again) the hp & Nm are different in RL and LFS.

[Lola Popeye]

okay sorry, i just havent really looked into race cars much, but it just seemed crazy that a race car could be faster than F1....or as fast

[tristancliffe]

Yeah but you have to remember that an F1 car is hugely traction limited up to 60mph, so it's not impossible to beat them with far less horsepower...

[Scawen]

A formula one car is said to do 0-100 mph (0-160 km/h) in less than 4 seconds, quite amazing acceleration... so our GTR cars have a much slower acceleration than a F1 car (not surprising as they are heavier and less powerful). F1 cars - with light weight, massive rear tyres and extremely powerful engine, are of course hard to beat on pure acceleration, by other cars that go round corners. Their launch control does not reduce their acceleration - it is designed to reduce wheelspin to an optimum level to get the maximum acceleration.

But (OT) F1 cars have so much downforce that their top speed is quite poor and on some tracks, the bikes go faster down the straight. I don't know what percentage of tracks the bikes can go faster, but presumably it would be anywhere that the track requires a high downforce setting, and has a long straight. In these cases the F1 cars sound terribly hindered, driving along the straight, stuck at a constant speed with all that power being used to beat the huge wind resistance.

[Fonnybone]

But (OT) F1 cars have so much downforce that their top speed is quite poor and on some tracks, the bikes go faster down the straight. I don't know what percentage of tracks the bikes can go faster, but presumably it would be anywhere that the track requires a high downforce setting, and has a long straight.

Interesting :) Glad to see you didn't lose your passion for bikes, soooo
you try making a bike yet ? Just wondering if you really intend to include
bikes in LFS or is that idea lost somewhere in the pile of 'stuff LFS could
have if time could stop for a few years' ? :p

Of course, if you don't answer i'll take it as a sign that you'd rather not
speak of it at this time ;) As usual.

[eindewege]

Uf1000 10.74, N.A
This is just too funny :D

[xaotik]

But (OT) F1 cars have so much downforce that their top speed is quite poor and on some tracks, the bikes go faster down the straight.

To continue on that OT tangent: Yeah, I think I had read that they have a drag coefficient somewhere between 0.7 and 1.1 depending on aero settings - a typical phonebooth would have around 2 I guess (extra reason they don't race them much) and a quick search yields that a Ferrari F50 has 0.372.

[tristancliffe]

I didn't think drag coefficients could go above 1.

*reads books to find out*

Whilst theoretically you could, I think it's highly unlikely...

To find empirical grag coefficient, Cw:

Cw = [6 m (a1-a2)] / [A (v1^2 - v2^2)]

where m = mass of vehicle
a1 is mean acceleration due to aero drag from high speed
a2 is mean acceleration due to aero drag from low speed
A = frontal area of car
v1 is mean velocity that high speed test was taken at
v2 is mean velocity that low speed test was taken at.

To find a and v, run the car on level ground, and coast from a certain speed to a certain speed (eg 100km/h to 95km/h) and measure the time. From that you can find the mean speed (v-u/2) and the mean acceleration (v-u/t). Repeat this at a lower speed (say 15 km/h to 10km/h and get the second values of a and v. Stick them in the formula and hey presto.

[xaotik]

I didn't think drag coefficients could go above 1.

*reads books to find out*

... if it didn't then parachutists would be in big trouble. But on the flipside people wouldn't lose so many umbrellas in a gale. (point being that the "base" Cd is calculated with a simple flat plate I think, so concave shapes logically should have a higher Cd than a simple flat surface).

[tristancliffe]

But surely a parachute slowsyour acceleration (unless it's an aerofoil parachute, but lets not go there, I'm talking single square or circle of fabric) only slows your acceleration and limits your terminal velocty. It doesn't imply a Cw of greater than 1 does it?

mass=75kg (person)
area=10m^2?
average velocity1 = 4m/s
average velocty2 = 10m/s
average acceleration1 = 0.2m/s/s
average acceleration2 = 1m/s/s

(very rough figures plucked from my imagination)

Hmmm, it would appear you're right, with a drag coefficient of 6.

Ignore me, but it was fun finding out wasn't it! :D

[Fonnybone]

Hmmm, it would appear you're right, with a drag coefficient of 6.

Ignore me, but it was fun finding out wasn't it! :D

Eh, Tristan, you DO know you don't have to post everything you do ;)
I'll be back in a few, i'm looking for that 'fun' you speak of... :p

[tristancliffe]

Eh, Tristan, you DO know you don't have to post everything you do ;)

Don't I?

*goes to toilet*
then
*goes to supermarket*

[v4forlife]

i just coughed

[B2B@300]

Don't I?

*goes to toilet*
then
*goes to supermarket*

Well at least your still on topic :D (Have a bit too much spare time)

[DodgeRacer]

A formula one car is said to do 0-100 mph (0-160 km/h) in less than 4 seconds, quite amazing acceleration... so our GTR cars have a much slower acceleration than a F1 car (not surprising as they are heavier and less powerful). F1 cars - with light weight, massive rear tyres and extremely powerful engine, are of course hard to beat on pure acceleration, by other cars that go round corners. Their launch control does not reduce their acceleration - it is designed to reduce wheelspin to an optimum level to get the maximum acceleration.

But (OT) F1 cars have so much downforce that their top speed is quite poor and on some tracks, the bikes go faster down the straight. I don't know what percentage of tracks the bikes can go faster, but presumably it would be anywhere that the track requires a high downforce setting, and has a long straight. In these cases the F1 cars sound terribly hindered, driving along the straight, stuck at a constant speed with all that power being used to beat the huge wind resistance.


malaysia, the moto gp bikes go blindingly fast down the two straights, the F1 cars have to carry a lot of downforce and they go a little slower..

[_Rob_]

http://rob.mm2c.com/Performance.jpg
My version from when I did it (some times are quite different :))

[Bob Smith]

There are some awesomely quick road cars out there, the TVR Speed 12 or Bugatti Veyron for instance.

Video of Bugatti Veyron - they take it to a drag strip (http://www.autoexpress.co.uk/evo/video_gallery/61410/bugatti_veyron.html) (the speeds the guy reads out are in km/h before anyone thinks "jesus that car got to 210mph in like 7 seconds"). Anyway not too shabby for an 1880kg car. :D

[Lola Popeye]

stop showing off that car, you already promised me that u'd get me one for christmas, do you want to buy it for everybody else as well? plus theres only 300 of em....keep it quite :)

[Fonnybone]

This thread got my brain stirring and i've made a small program to do
various acceleration tests, like Gmeter, but without using any of the
InSim/OutSim stuff, so it's got an update rate around 1ms ;) It can
only do steps of 10ms from what i see, but then again, didn't Scawen
say the physics engine is running at 100Hz ?

It's not really done yet, but if you guys are interested, i could post a
test version here. I got it do the speed tess fine and last night before
going to bad, i had managed to get the distance test working. I'm
figuring out distance by using Speed*Time, so we'll see how well
that works, looked good last night...All that's left now is to make it
log the time/speed data to a text file. Then i'll add a 'plotter' to see
those graph, both 'offline' and in real-time.


Edit: Just did 3 runs in the FZR and got 0-100kmh times of : 3.300, 3.190
and 3.040 seconds ;) The distance tests aren't accurate though, it stops before
the 1/4mile in LFS, i got 8 seconds 3 times in a row, LFS gives me more like 10+
seconds. Let me see if i can find more usefull data like car position of something..

[Bob Smith]

Hmm, with the acceleration code I put into GRC with the last big update it would be useful for me to get some hard numbers to compare with so I can fine tune my physics data.

[Fonnybone]

I'm an eternal perfectionist and i don't think ill ever be 'happy'
about an app i release, so, i'll try to simplify this one even more
and perhaps be able to release something tomorrow, saturday.

What gets to me is that, like all my apps, the code is pretty
much done, but i spend a LOT of time on the details...

[Tweaker]

Details are goooood, I can wait :p

[Fonnybone]

http://www.lfsforum.net/showthread.php?p=39196#post39196

:) As promised.