The online racing simulator
#1 - Pasci
Drive-through penalty with active speed limiter
I've posted that problem already in the thread of the mod (https://www.lfs.net/forum/thread/96405-E-CHALLENGER). But I'm not sure if this really a problem of the mod or LFS itself.

Perhaps someone can try/reproduce that too?

Issue with (at least - not tested any other car)
Car/Mod: E-Challenger or E-Challenger Evo (can reproduce with both cars)
Track: Blackwood Historic [Reverse]

Proceed:
Out of the garage with the speed limiter active and drive towards the track on the throttle. On the slightly sloping route in the pit lane, the speed increases to over 80 km/h despite the speed limiter and causes a drive-through penalty.

Maybe this is legitimate, but it surprised me yesterday when it happened to me.
Hello there.

I can confirm this is happening and I believe I know why/how, so I'll try to explain:

The way the limiter works is it cuts the throttle to stop the car from accelerating. It however does not engage the brakes to slow the car in any way. In this particular scenario when the car gets on the downhill slope the limiter stops the car from active acceleration, however as the car keeps rolling down the slope, it gains speed from gravitational forces. While this is obvious with EVs (such as both E-Challengers) due to their very low engine resistance/inertia, you can reproduce it with combustion cars as well. Simply leave the pits and go at the limiter towards the slope. Once at slope, either engage the clutch or go to neutral (this removes the engine resistance from the equation) and the car will start gaining speed despite being at the limiter as well.

So this 'issue' was always there, but was not obvious until EVs were introduced in LFS.
I'm not sure if real life pit limiter would use brakes to slow the car down though, I think this would probably happen irl as well. Shrug
I beleive this is the fault of the speed limiter routine in LFS.

If it doesn't have already, it should have a PID loop. It may also be that it is simply not reacting fast enough. Scawen needs to retune some parameters for it. It has 3 terms, proportional, integral and differential. Most probably integral needs incresing a little bit.
Quote from michal 1279 :I'm not sure if real life pit limiter would use brakes to slow the car down though, I think this would probably happen irl as well. Shrug

I looked at aftermarket pit limiters that I found in random shops on the internet.
None of those mentioned the use of brakes, all just limit throttle position or engine RPM.
For professional motorsport I found nothing clear in any rules, however several websites say something like "The limiter only prevents the car accelerating beyond that speed once it's already below it."

I think tweaking the control loop does not solve this.
The car can only slown down at a certain rate from friction etc.
If the acceleration from a slope or wind (or spinning tires suddenly gaining grip) exceeds that rate then there is nothing that the system can do, no matter how fast or soon it closes the throttle.
Only a larger safety margin would help for some situations. (limit to 78km/h instead of 79.xx or whatever)
If the downward slope is long and steep enough then some vehicles might always exceed the speed limit.

random fun fact from F1 rulebook:
Quote :One gear change is permitted after the race or sprint session has started and before the car
speed has reached 80km/h, provided every gear fitted to the car is capable of achieving at
least 80km/h at 15,000rpm.

With some cars in LFS it is popular to adjust the 1st gear ratio so that it will reach a topspeed just under the speed limit. (79.9 km/h)
According to real life F1 rules that trick would be illegal.

FGED GREDG RDFGDR GSFDG