Jorah

That's true. There is a small reduction before the differential and one more in the first gear, but the ratio of the turntable to small gear is really big. This is perhaps the biggest drawback of a solution like this, because it also means there is more friction to overcome.

Hi, I want to present my alternate limousine model for 42108. The model has some interesting functions. At first there is a V8 engine driven by the back wheels. The twist is that the differential in the back is build, using the large turntable to house the inner gears! Secondly there is a gear shift incorporated before the engine, and it works by really shifting a gear around! There are two speeds and a neutral gear. Normally it would be easy to achieve these things with the special parts that exist for this, but they are not part of the set, and so I had to come up with more unusual solutions. See the render of the functions core here: Furthermore the front wheels have steering, operated from the roof. But the steering wheel is also connected to steer. The doors, hood and trunk all can be opened. The design process was quite complex. I started experimenting around with real bricks, but everything did not quite fit together. So I had to use digital building in parallel, because it is easier this way when the internals have to be moved around a lot. In the end I constantly switched between both building methods, always reevaluating solutions. The resulting base structure is more complex than anything I would have been able to produce by just tinkering around with parts. Here is an animation of the different components: (building steps are different and easier) Building instructions can be bought at rebrickable and I hope that everyone who attempts this model will have a rewarding building experience.