Jolt Vehicle Tuning Guide
jMonkeyEngine Hub
May 12, 2026
Found an issue with my clutch system. Fortunately i am developing with a car that would show it. My clutch allows for slip and calculates the torque transfer, since i have not real knowledge on how modern clutches actually work and i try to avoid car software like a clutch controller.
In regular tests everything was working perfectly. I failed to add a top speed test since that shows the problem.
At 247kmh the aero drag is higher then the clutch torque. As soon as you shift up and the clutch slips a bit, car gets slowed down due to drag, but engine rpm is rising. As a result the clutch is not able to deliver the torque needed to accelerate the car anymore and stays in a slipping state.
The solution was to transfer torque both ways, so it would eventually bring the rpm down.
The downside is that without manual or controller based clutching during braking or downshifting now the engine does generate torque in those situations.
Now with the probably more correct clutch math the 918 is able to reach 357kmh before reaching aero/torque equilibrium. Compared to the specified top speed of 345 my calculations seem not to be far of.
So far so good. Currently working on some AI pilots which is also very new for me. Test track is Mount Panorama Circuit, official best time for a 918 spider is 2:04. my best ai currently requires 3:38. But i at least managed to make it drive quite save around the track.
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