Installing hyper 212 evo on already built pc

Hi, I have a cooler master storm trooper case, so I do have access to behind the CPU,
I was wondering if I would be able to install the hyper 212 evo on my computer as I am over clocking a bit with stock cpu cooling and unless the fans are running on full in the case the system can becoming unstable. I set the multiplyer at 45, and touched nothing else. CPU temps usually stay between 50 - 90, when playing games like skyrim usually around the 80 mark. How much higher could my multiplyer be if I put on my hyper 212 evo?