Jolt Vehicle Tuning Guide

A update with another key finding. I actually hit the first limitation build into jolt. With transmission in automatic mode clutch friction is overwritten. It simulates correctly friction slip while shifting, but after the release time it always fully locked the wheels to the engine. Usually not a issue, but it was the root cause the ABS system did not work correctly and my breaking times where off. It turns out, it took 0.8 seconds for a locked wheel to regain grip since it had to overcome the total inertia of the transmission and engine.

I moved away from using the automatic transmission, and implemented a autoshift assist. It does the same thing as the jolt build in, but it allows full control over clutch and shift times.

Now ABS is working way better and i am in fighting distance with real world data. Also i can set the clutch friction to 0 when breaking, so i can have correct coasting and i can disengage the transmission/motor on hard breaks.

An additional benefit is that i was able to implement a very basic torque converter for the cars that have such systems, like the s63 and the db11. It nearly took away 2second in the 0-100 tests.

As for cornering issue, the telemetry says that i am actually able to pull enough lateral g’s to match real world rars. It does not feel like it, but i have 0 experience riding such cars on actual tracks. I have ridden some nice cars on an ice lake and have some carting experience, but nothing that would allow me to estimate the correctness beside synthetic tests and real world data found on the net.

The AWD cars are now in the correct range in accelaration tests, RWD and breaking is still off, so that suggests something is not correct on the weight transfer side. i should have slightly more grip on the rear wheels when accelerating and more grip on the front when breaking.

    0-100 km/h (s)               60Hz   120Hz   240Hz    Real
  porsche/gt4                  5.38    5.15    5.29    4.40
  porsche/gt3rs                4.47    2.86    2.85    3.20
  porsche/918                  3.42    2.32    2.29    2.60
  lamborghini/gallardo         3.35    2.90    2.97    3.70
  lamborghini/huracan          3.10    2.91    3.04    2.90
  mclaren/senna                3.70    3.51    3.64    2.80
  mercedes_amg/s63_brabus      4.07    3.31    3.39    3.50
  aston_martin/db11            6.07    5.31    5.44    4.00

  100-0 km/h (m)               60Hz   120Hz   240Hz    Real
  porsche/gt4                  35.7    36.7    35.7    32.0
  porsche/gt3rs                27.9    32.9    32.8    28.0
  porsche/918                  33.6    32.9    33.0    30.0
  lamborghini/gallardo         40.6    40.5    40.5    33.0
  lamborghini/huracan          41.6    41.5    41.5    30.0
  mclaren/senna                28.9    28.5    28.4    28.5
  mercedes_amg/s63_brabus      41.0    40.3    40.6    36.0
  aston_martin/db11            35.4    36.2    40.8    32.0