CM 212+ hyper plus with 1 stock fan locate to the right side (ram side) - pushing hot air toward the back of the case
1 front 120mm stock fan from cooler master 430 - pulling cool air inside the case
1 back 120mm artic cool from microcenter - pushing hot air outside
Idle temp: 39-35-35-36
Prime95 after 15min: 55-58-58-58
1/are theese number normal?
(I did notice when installing the after market cooler, i couldnt completely tighten the screw, and the heatsink was able to slightly laterally turn, just a light tad the heatsink rotates...but there is no visible gap the processor and heatsink.)
2/The bottom line question is, does CM 212+ beat the stock cpu fan ?
The problem here is your case, however those temperatures do seem a bit high. Try getting another fan for a push pull configuration. But another possibility, is you added too much thermal paste. The temps you are getting are the temps I get when overclocked.