Lately I've been thinking a lot about the possible cause of people having trouble with the tire physics of LFS.

From what i've understood, most of the complaints are due to "lack" of grip mainly during corner exits and corner entry.

During steady turns the car handling seems (IMHO) very realistic, but when we have (rapid) changes in throttle... people start talking about "strange" feeling with the car and lots of (difficult to explain) "sensations" of something happening not quite right.

IMHO is not much (or maybe mainly not related to...) a problem with the tyre model, but instead more something related to the way engine and throttle are modelled in LFS.

In fact, very much like in real life racing, it is the throttle control (and brake) that differentiate the fast racers from the average racers.
In LFS I think this is even more evident. Lots of beginners have trouble with throttle and low speed spins!
In this respect FWD is easier than RWD and as such recieves less critiques.

Some time ago a very interesting forum thread regarding differentials gave Scawen a good suggestion on some possible solutions (thanks to Todd Wasson: http://forum.rscnet.org/showthread.php?t=197274 ).

My idea is that there is still something that can be improved in the way the engine/throttle is modelled.
Real engines have some "inertia" when you apply throttle. Let's say that, in neutral gear, you put the throttle pedal on a mid position... the engine rpms will rise, but this will not be istantaneous. It will take some time (depending on various different factors) and than wille stabilise.
The same will happen when you release the pedal... rpms will go to minimum, but with a delay.
I expect this behaviour to be different with changing of engine type, gearbox, differential and (generally speaking) different car.

In LFS this behaviour is absent. If you step on the gas pedal (every car i tried) with neutral gear, the rpms will immediately rise and settle. When you release the pedal, rpms will immediately drop.
There is no evident (or maybe only minimal) sign of the "inertia" from the engine and the natural delay that should occur between the imput (throttle) and the output (rpm).

This makes me think that power apply/release will reach the tyres much quicker than in reality... with the consequence of possible (undesired) tyre spin. Not only during the first imput, but also during the corrections applied.

Fast LFS racers develop a good feeling for the "gas pedal" and are able to apply smooth acceleration (with small or no tyre spin) and also very "appropriate" throttle corrections to recover from unusual departures.
This obviously applies also to real racing, but my feeling is that in LFS is way more difficoult than real life (and due to lack of G forces!).

Just my opinion....

You might be on to something here. It seems that the engine internals would be very light (something I'd understand with the racecars), and that definitely would cause some tricky handling like the driving wheels locking up when lifting off. And add to that the (oh so often used) fact that we can't feel what the car is doing.

:eclipseeh


:ambulance

Hmm, I'm not sure but it feels pretty delayed to me

Honestly, the real car's I've tried dont have inmediate rises and drops of RPM when throttle is applied, the RPM increase and decrease with a delay. This depends on the force needed to turn all the moving engine parts and drivetrain around, and it depends on the engine power.
In LFS, I see just as much of this delay, wich also depends on power.

Sounds like you're talking about the flywheel. I don't know if/how the flywheel is moddeled in LFS. Might be interesting for Scawen to have a look at. (The FXR and XRR could certainly use a lighter flywheel..)

Here's some interesting info on the subject: http://www.geocities.com/MotorCity/7177/flywheel.html

Quote from AndroidXP :

Hmm, I'm not sure but it feels pretty delayed to me

I did some more testing and indeed you are right...
It is delayed and it has different rise/falloff times on the different cars in LFS.

...so maybe this is not the problem...

I can say that the flywheel definately is modelled in LFS, simply because it's available to play with in LFS Tweak. Use high values and the revs are REALLY slow to build up. Use a huge number and give the engine silly power and you can make the car flip/roll.

Proof: Post #9

awsome videos

Quote from Bob Smith :

I can say that the flywheel definately is modelled in LFS, simply because it's available to play with in LFS Tweak. Use high values and the revs are REALLY slow to build up. Use a huge number and give the engine silly power and you can make the car flip/roll.

Proof: Post #9

Ah yes, didn't know there was an option for it in LFS Tweak