Performance issues in a large modded base rarely come from one setting alone. The useful approach is to measure when lag appears, reduce constantly active systems, and compare the same location with changes made one at a time.
Separate client FPS from server tick lag
Low frame rate and slow server ticks need different fixes. First determine whether visual rendering is slow, interactions are delayed, or both.
Reduce unnecessary active devices
Security devices that constantly check nearby entities or states can add work when used at very high density. Keep protection focused around actual entry points and critical rooms.
Test redstone and automation interactions
Large redstone networks, chunk loaders or automation mods can amplify the cost of security systems. Disable or isolate nearby systems temporarily to identify interactions.
Use sensible Java and launcher settings
Allocate enough memory for the complete modpack without assigning extreme amounts that create long garbage-collection pauses. Keep Java appropriate for your Minecraft and loader generation.
Benchmark in a copy
Use a copied world and measure the same location before and after each change. A repeatable test is more useful than changing several settings based on a single lag spike.
Next step
When you are ready to install, return to the main Security Craft Mod download section after checking that your game version, loader and intended build match. For broader setup context, compare this guide with the installation setup guide.