Negative forward drafting, ghost throttle acceleration,

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1

This issue was FIXED then immediately after this recent update the ‘GHOST THROTTLE’ returned there is no throttle input shown but the revs haywire rise with no throttle input it is ‘roll in handover fade in’ again, for the 1st of March Marring thats also been occuring elsewhere and locally.

Negative forward drafting;
In what world of physics does the forward momentum ‘drafting’ push ones vehicle in front? From like a tailgating point of view its perceivable, but, if the vehicle in front is sideways the approaching traffic from behind create ‘negative forward drafting’ from ten cars away or 50m? from behind, pushing sideways motors off balance as they approach from behind, an effect not a possible physical phenomena in reality.

2

Can someone please translate this for me?
I don’t get what you’re talking about.

3

Ok;
The phenomenon of “Forward Drafting”, where a trailing car pushes a leading car forward from a distance of 50 meters behind in a racing simulation, is physically impossible in real-world aerodynamics due to the fundamental principles of fluid dynamics and the nature of airflow around moving objects. Here’s why:

1. Real-World Drafting (Slipstreaming) Mechanics

  • In reality, drafting occurs when a trailing car moves into the low-pressure wake created by the leading car. This reduces aerodynamic drag on the trailing car, allowing it to use less power to maintain or increase speed.
  • The lead car does not receive any forward push from the trailing car unless there is physical contact (bump drafting).
  • Any aerodynamic interaction between cars generally results in a negative effect (increased turbulence or rear-end instability for the lead car).

2. The Impossible “Negative Forward Drafting” in the Sim

  • In the scenario you described, a car that is 50 meters behind somehow pushing the car ahead is an aerodynamic paradox.
  • Airflow naturally moves from high pressure to low pressure. The trailing car’s wake is a region of disturbed, turbulent, lower-energy air, which would cause drag, not thrust, on the lead car.
  • There is no known physical mechanism by which a car could generate a thrust force on another vehicle from such a distance without direct propulsion (e.g., a jet stream or rocket thrust, which race cars do not have).

3. Possible Causes in the Simulation (Game Physics Flaw)

This effect is likely caused by incorrect aerodynamic modeling or a physics bug in the simulation. Some possible errors include:

  • Reversed Wake Effects: The game might incorrectly apply a suction force from behind, treating the lead car as if it is being “pushed” instead of being resisted.
  • Artificial Speed Boosts (Netcode or Assist Features): Some racing games artificially adjust speeds for balance, which could create an illusion of forward drafting.
  • Excessive Airflow Influence in the Code: A miscalculation in how air pressure zones are simulated could lead to erroneous acceleration of the lead car when a trailing car enters a specific proximity.

Conclusion

The phenomenon of “Forward Drafting” (negative forward drafting) in a racing simulation is a clear violation of real-world physics. It likely results from a flawed simulation of aerodynamic forces rather than any legitimate aerodynamic principle. In reality, a trailing vehicle can reduce its own drag via drafting but cannot apply forward thrust to a lead car without direct contact or an external force (like wind or a propulsive system).

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4

Thanks a lot for that.
Now i understand it, after reading trough all the points, i could imagine it’s actually the “Artificial Speed Boost” that happens in Forza.
We’ll see if we get a reply about this.

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5

On Series X with a fanatec csl dd and I have a similar issue with the “ghost” throttle.

Anytime I am driving near laggy players or experience the frame drop in corners where it happens commonly, the game will max out the throttle despite there being no input. I have to either slam on the brakes or hit the clutch paddle to make it stop reading throttle input when there is none.

This ruins races because it happens in corners predominantly so it will push the car off track.

Also it happens when a laggy player crashes into me during MP races. The throttle will he pinned despite no input. A hard brake or clutch paddle will rectify this but sometimes needs to be done several times.