I also noticed that the axles stretch if you watch closely, and I know that axles try to return to their original position, so maybe its like some sort of "hinge constant" engine, it's just a theory.
In real life there would be a Z axis, but it is a 2D simulator, so I only made an X and Y axis. I was also thinking of making the tip like the brush tool or something like that kind.
I made one too, and they are by coincidence the same size, and mine only having a scripted throttle is a lot faster than yours, mine does not even have a gearbox.
Check it out at: http://www.algodoo.com/algobox/details.php?id=72845
The engines that you made, like this one and the turbine, are only possible on Algodoo, they only work because the ball spawns and collision makes it pop out, thats why its sooooo hard to stop the motor. In real life you would need compression too. But atleast they work... 10/10
I was messing with the scripts (like I do with all) and I made it so the balls had infinite size, then I made it bigger until the motor glitched and the rotors flew off. Only 3 gray circles were left, and I was getting about 146 Rads. I always end up with crazy results...
10/10
I have a fully custom PC that runs at 6.5 GHz and has 8-Cores, 32 GB RAM and 2 GB graphicsa card, my scenes run like normal at 1200 Hz but when theres water it gets a little slow.