As previously noted, to get max speed minecarts in Minecraft at the moment through the use of the /gamerule command, you'll need to be playing on Snapshot 24w33a or above and also have cheats enabled.

How to generate your MCStacker pixel art in Minecraft Java with a datapack A command block generating pixel art in Minecraft: Java Edition (Image via Mojang) ...

For example, it can detect block placement, block removal, fluid flow, and much more. But making this block can be a bit of a process. Read this guide to learn how to make an Observer in Minecraft.