First, you must confirm what Block 189 is in YOUR pack.
To understand how a fast block place mod works, you must first understand how vanilla Minecraft 1.8.9 handles right-click inputs. fast block place mod 189 work
By default, vanilla Minecraft 1.8.9 forces a 4-tick delay (about 200 milliseconds) between block placements if you simply hold down your right-click button. First, you must confirm what Block 189 is in YOUR pack