there are two upgrades currently available for the Routing Network.
Firstly, the Basic Routing Logic Upgrade increases the total amount of items transferred per operation. (once per second, but see overleaf). By default, the network will transfer 16 items at a time, but each of these will raise that cap by 8.
These upgrades stack to 16, allowing for a sum total of 144 items to be transferred per second. Note that this can be split over multiple stacks, if many different items need to be transferred at once.
The second upgrade is the Basic Routing Speed Upgrade, which increases the rate at which items are transferred. The default rate is one operation every 20 ticks (1 second), but each speed upgrade will bring this down by 1 tick, to a maximum of every tick with 19 upgrades.
they stack to 19? that feels ... wrong, somehow, but it was this or alter the universe such that everything ticks 65 times a second, and that would have made people even more upset.