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Bob Smith
S3 licensed
Moderator
From testing in LFS, they decided just to add an undertray to the MRT6, and not the wings. At least, that's what I recall. The in-game car was never intended to be released to the public.
Bob Smith
S3 licensed
Moderator
Quote from Nick7 :Add rolling resistance of tyre, and ofc - resistance of going thru air, etc, etc...

Intentionally. For the purposes of this comparison, rolling resistance and air drag are identical, thus while the acceleration figures given are too high, it will reduce them both by the (almost) same amount, so it's still acceptable to compare the differences between them, which is what we're interested in here.

Quote from Nick7 :So in the end, difference is miniscule.

If you add in an arbitrary resistance force (comparable to travelling faster), you'll see that in fact, the absolute acceleration benefit increases (albeit marginally), and the relative benefit can increase significantly.
Bob Smith
S3 licensed
Moderator
Quote from rageshgr :1) A worn out tire due to its lessened radius, will have lesser mass and more importantly lesser moment of inertia. So it is easier to rotate that wheel with the same torque. This I am sure has implication on acceleration. Hence the reduction in linear velocity due to diameter decrease and increase in angular velocity(RPMs of the tire) due to lessened mass and lessened moment of inertia may try to cancel each other

You can work this out. Acceleration can be calculated by a=f/m, where m is this case is translational inertia, rather than simply mass, and force is engine torque over wheel radius.

I took my X-Type as an example, comparing new tyres to those with a full 8mm of wear, the car ends up approximately 2% faster in 2nd gear (higher gears give a larger benefit as the engine inertia tumbels).

It looks like it's always going to be that the vehicle accelerates faster as the tyre wears (at least for typical values). I've attached a spreadsheet you can experiment with. The wheel inertia calculation is very simplified but it will do for now. I could make it generate the wheel masses and inertias for worn and unworn but it's too late and I'm very sleepy right now.

Quote from rageshgr :2) Theoretically this lessened mass and lessened moment of inertia of the wheel should improve top speed too I believe, hence trying to cancel out the reduction in speed due to lessened diameter. But I am not sure about this second point.

Umm.... no. The only effect on top speed will come from the changed engine velocity and thus power output.
Bob Smith
S3 licensed
Moderator
Well that's it, I'm not posting here any more then.

No seriously, help is always useful. Show respect!

I'd say "good luck!" but I can say from personal experience a better sentiment is "have patience!"
Bob Smith
S3 licensed
Moderator
Quote from Kid222 :How the feck is this thread still open.

Because it's damn amusing. I'm sure I've read this before years ago, although back then it was about wheel view, rather than force "mode".

If you're faster with it on, that's great, but I assure it offers no more advantage to changing the FOV or any other camera related setting. Some people even race with the chase cam. We may mock them for being childish and breaking immersion but to be fair, they do have better vision around the car, so as long as they don't crash into me, I really don't care.

Nobody tell this guy about button clutches, macros or hacks. Then he might even have a point and it wouldn't be quite entertaining then.
Bob Smith
S3 licensed
Moderator
Quote from col :Look up "brush tyre models" - that's what the current LFS tyre physics is a variation of - not Pacejka, which I understand is getting a bit long in the tooth.

Scawen discusses current LFS tyre approach here

You misinterperet. The current model you're all driving around on is an empirically based model that Scawen invented, perhaps similar to Pacejka (I don't know the details). I don't know if this is the same basic model that Scawen has been tweaking since 2002, or if he's ever started over.

The first new tyre model Scawen wrote was based on brush model theory. That model never made public as, although better in some areas, went very wrong when taken outside the areas covered by the assumptions and simplifications needed to make it work. So Scawen started a second new tyre model, based more on tread model theory, however it's ended up too slow for real time use in game, so there's now a third new tyre model, that aims to give results similar to the tread model, yet be sufficiently simpler to run in real time. That's no easy challenge.
Bob Smith
S3 licensed
Moderator
Quote from Zero7 :And oh, Bob, if you're reading this, great stuff - thanks. I think we should have road going sets in official releases of LFS.

You're welcome. Thankfully, you're not the only one who thinks this. Scawen is in agreement also. We'll see what the future brings.
Bob Smith
S3 licensed
Moderator
Check the date of my data. From before rev-limiters.
Bob Smith
S3 licensed
Moderator
Broken record alert:
Quote :This server is currently not licensed. Please contact the server administrator. Other services available on this server such as web services are likely functioning normally. (Cannot read license file)

Bob Smith
S3 licensed
Moderator
Webserver fallen over again?
Bob Smith
S3 licensed
Moderator
I'm sure cPanel was working very recently, now I'm back to my old friend "Cannot read license file"...
Bob Smith
S3 licensed
Moderator
No cPanel access here either (cannot read licence file). Noticed it down a little while ago, has it really been down all this time?
Bob Smith
S3 licensed
Moderator
Quote from KassadGLA :I don't know how :/ And actually I have a Pentium III@550mhz 4mb graphic card... so is hard make gifs with it

The GIF format was created in 1989 and the animation extension was added by Netscape in 1996, thus pre-dating your PC by 3 years. So it should have no problems.
Bob Smith
S3 licensed
Moderator
Quote from three_jump :Finally managed to finish my small report...
http://www.triple7racing.net/content/view/182/1/

Ooh, I get two new nicknames. I should be honoured.

Thanks for the write up though, it was nice to read.
Bob Smith
S3 licensed
Moderator
It works, yay! If only a trial licence, which will no doubt expire soon?
Bob Smith
S3 licensed
Moderator
Quote from franky500 :Based on the e-mail i got back, It will be sorted anytime from 2 - 24 hours.

Up to 29 hours now. Is this likely to be resolved over the weekend? I'm putting out job applications with a link to a web portfolio that I'm making, it would be nice if come Monday morning I had actually created the subdomain I'm linking to.
Bob Smith
S3 licensed
Moderator
Quote from Matrixi :The physics didn't look all that convincing in the trailer either.

Well the cars look like toy cars with almost no inertia. Which is exactly what they are, so I'd say that's good. If they looked anything like regular cars in motion there be a real problem!
Bob Smith
S3 licensed
Moderator
Thanks for letting me know you're on the case.
Bob Smith
S3 licensed
Moderator
cPanel is bust again (Cannot read license file).
Bob Smith
S3 licensed
Moderator
Sorry, didn't notice this reply, should really subscribe to this thread.

If you post more specific details of the problem they I may be able to assist.
Bob Smith
S3 licensed
Moderator
Some more information about what's in your pack would be useful.
Bob Smith
S3 licensed
Moderator
Quote from ColeusRattus :And 3 hours for 12€ is quite okay.

Don't let iRacing hear you say that.
Bob Smith
S3 licensed
Moderator
Agreed. Real engines make music, not noise.
Bob Smith
S3 licensed
Moderator
I can't believe I'm going to dignify this post with a response but since I'm anally retentive...
Quote from Racer X NZ :it will explode spectacually somewhere from 5000 rpm up.

Truck engines can be toast at half that rate.
Bob Smith
S3 licensed
Moderator
If there is an engaged clutch between the engine and gearbox (i.e. in a manual transmission, or auto with lock up), then the engine will continue to reciprocate faster and faster. A rev limiter may ensure a lack of fuel but it won't stop valve float (which even without combustion will still have an effect on engine braking), or your con rods from snapping from the increased stress due to the ever faster moving pistons applying larger forces to them. I don't see heat being a problem. If you kept the rpm very high and the conrods didn't break, then there is the possibility of the the valve springs fatiguing and failing, or without enough bounce, colliding with the pistons.

With just a torque converter, there is no direct connection between the engine and wheels, but the fluid will only allow so much slip, so you'll get the same problem, only it'll happen at a slightly (10%?) higher speed.
FGED GREDG RDFGDR GSFDG