Thanks again for Your explanations. 
After a complete reinstall of Gear City I started a new game under 1.13 and did some testing with gearboxes. I let my researchers develop one gearbox after the other, all 3 gear manual generic gearboxes with every slider maxed out. After 4 1/2 yrs ingame I had 9 gearboxes designed and every one of them had an overall rating of 11/100 after development started.
One would assume that researching so many gearboxes in such a short time frame should give the researchers a nice amount of knowledge which would raise the rating of every new designed gearbox, but nope, the overall rating of 11 seems to be set in stone. The only thing that changed significantly were the unit costs that rose by approximately 50% (first gearbox had a unit price of 165$ after release, the last one 246$).
Bankruptcy prevented me from continuing the tests, but I assume that even 20 more gearboxes wouldn't have raised the overall rating to a value higher than 11/100.
After a complete reinstall of Gear City I started a new game under 1.13 and did some testing with gearboxes. I let my researchers develop one gearbox after the other, all 3 gear manual generic gearboxes with every slider maxed out. After 4 1/2 yrs ingame I had 9 gearboxes designed and every one of them had an overall rating of 11/100 after development started.
One would assume that researching so many gearboxes in such a short time frame should give the researchers a nice amount of knowledge which would raise the rating of every new designed gearbox, but nope, the overall rating of 11 seems to be set in stone. The only thing that changed significantly were the unit costs that rose by approximately 50% (first gearbox had a unit price of 165$ after release, the last one 246$).
Bankruptcy prevented me from continuing the tests, but I assume that even 20 more gearboxes wouldn't have raised the overall rating to a value higher than 11/100.