Hi there,
I’ve been trying to mod my 415 to CS. This is how it got so far. Still have to change the front belt and pulley. Still didn’t find a suiteable belt to fit with a larger pulley.
The centerpulley is changed with a HB set. To the back it has a 18T pulley, and to the front it has a 16T pulley.
This here’s the back differential with a TA04 pulley on it. I had to tighten the drivebelt up with extra tensioners. It may look a bit crappy but it works fine.


Also you need to change the positioning of the tires when they are under angle of steering. The tire closest to the driving circle has a shorter radius of steering than the one that’s on the outer circle. This is called Ackermann. When you are modding your chassis for countersteer, you have to minimize, if not, completely remove the ackermann from your steering house. This is a very tricky mod, but the internet is full of alternatives.
I’ve chosen to make it by myself. Still need to finish it, but it works just fine.

Please leave a comment if you need info!