Engine power calculation

So I was wondering how was the power of engines along with their speed and all calculated in game cause it doesnt make sense that a 150 kg motorbike that has a 1100cc v twin can only reach 66km/h without destroying the engine and it isnt logical either that a car with a 8 liter diesel v8 can reach speeds up to 600km/h (albeit not safely but still).
Anyone has the answer?

Max velocity is total_power * 80.

Safe velocity is (assuming one engine):
power * type_constant * k_mass * k_dynamics * 80

type_constant is 0.6 for gas, 0.65 for diesel, 0.9 for electric

k_mass is currently rather forgiving, because vehicle components are quite light. A car weights 750 kg - compare to real life car that is closer to 3000 kg.
k_dynamics is k_aerodynamics * k_friction
k_friction is usually rather high (as in, doesn’t impair much). Exceptions are vehicles with huge wheel area, like rollers.
k_aerodynamics is also really forgiving: you need a vehicle with 7 tile width to get it down below 0.5

Is there any way to increase power through accessories (e.g. superchargers, turbos, or engine kits) considering alternators reduce it?

At the moment no.
It was proposed, but the conclusion was: the stock vehicles would most likely have those already, so they would be easy to acquire, wouldn’t offer any real customization and thus would be redundant.

Well, all the engines could always be naturally aspirated, with the exception of non-V12 sports wars which would have such accessories to be sporty, for example.
And bikes have to be viable somehow. Going everywhere at 60 cause otherwise your engine explodes aint no fun.

Make a balancing thread on drawing board or as an issue on github and suggest changes.
The balancing isn’t strict here, all good, implementable ideas will be considered.

So far I haven’t looked into trying to balance vehicle speeds very much for two reasons.

  1. The highest benefit is achieved by going faster than the fastest enemy, anything beyond that is mostly cosmetic, and most vehicles should and can achieve that speed.
  2. The biggest missing element in the vehicle system is traction, you can go exactly as fast on turf as you can on asphalt, which is just silly, this dwarfs any problems with power calculations.