Modify Radius and Spirals

Good evening, I just started using Dynamo and a question has arisen if I have an alignment already created with spokes, if I want to modify them by giving them a minimum value, how could that be possible with Dynamo.

I want the radius of 388 to become 400 round every 5 meters, the radius of 149 to become 150 and be spiral; in the same way the radius of 40 becomes 150 and is now a spiral

This would be a flow chart of what I am trying to do