i'm not a guru, but this isn't hard to figure out.
the one on the left is the fans mounted up front as it is running hotter (assuming the
numbers on the left are ° marks) as it is peaking at about 79°-81° the one on the right
in running 74°-76° with just the exhaust and radiator in push exhaust.
and so you ask why run intake fans at all if they are going to overheat my case?
you should really check out the thread on air case cooling:
you might even receive better by moving the radiator to the forward mount, and utilize the
side panel fan(s) mount(s). reasons are the front fans are drawing air in, but that is all, the
upper fans are pulling phantom air (more than likely from the side panel) and cooling the
upper half (area above video card) because of the strong pull from the exhaust fans.
the front fans are barely functional past 150-180mm after the front fan. and if you have any
obstacles behind them, you just have a bigger problem.
the idea is alot of filtered cold air in and alot of hot air out.
just rough thought, your case is 19.1 x 8.3 x 17.7 = 2806in³ or 234ft³
your 140mm fans are @ 12v able to produce 69cfm each = 138cfm (way under capacity)
meaning it takes 102sec to just fill your case up with new air.
your noctua fans are @ 12v are 59cfm (S12B) and 55cfm (F12) = 114cfm (way under capacity)
meaning it takes 123sec to pull all of the air of of the case.