Tony1337 :
Just got a kit of 2 x 4 GB of Corsair ram could I plug it in my system that already has a kit of 2 x 4 GB of Avexir ram that runs at the same speed and timings without running into too much trouble?
You more than likely will have issues Tony, especially from different manufacturers.
Read this informative article: https://rog.asus.com/forum/showthread.php?57038-Don%92t-combine-memory-kits!-The-meat-and-potatoes-overview.
Forums are full of frustrated attempts trying to mix kits. It's just not worth it.
Keep your existing kit for spares and buy a single kit the size and frequency you need. Always best to select kits from the Manufacturers QVL list that have been tested in conjunction with your MB.