One of the tricks to speed up your WordPress site is to hack away at the unessential! 🙂 This implies that you don’t need all your plugins loading on all your pages and posts. That slows down your site!
Some of the plugins have a specific purpose that you need only on certain pages and posts. Check out this great article I ran into which describes how to disable plugins from loading on certain pages:
How to Disable WordPress Plugins From Loading on Specific Pages and Posts