[Username_1]

I have a CM Storm Enforcer ( which I regret now having seen the Zalman Z11) and was wondering if it would be a good idea to get either some top exhaust fans, replace the back exhaust fan, or even get a aftermarket cpu cooler?

ATM temps are usually fine, but sometimes the CPU easily goes over 45C when Im not even gaming, and when I do it goes over 50.

 

[Tyree]

Brand & Model of Mobo-CPU-RAM-Graphics-PSU.
One 120mm in front & rear is usually fine. Adding top and especially side mounted fans commonly causes turbulence and disrupt the desired front to rear airflow.
OEM CPU heatsink/fan is fine if no OC is applied.

 

[Username_1]

Asus P8Z77 V-LX
Intel i5 3750K (may overclock, although I think it was you who said that it doesn't make to much of a difference)
Corsair Vengeance Ram
EVGA 670 FTW Sig II
Corsair TX 750 V2

 

[Tyree]

I see nothing that would require any extra cooling fans with that case.
OC'ing is rather pointless with new CPU's.