It should be plenty. My titans at 1.21V and 1215MHz core hit a whopping 41C after 3 hours of Valley. Crysis 3 puts the cards at 38C and the 3770k at 60C with 1.3V through it. I still have air in my loop, too.
I use these components:
Koolance RP-401x2 Reservoir
5x EK PSC 90* Rotary Fittings
8x Swiftech 45* Rotary fittings
1x Koolance 2-3 Slot Bridge
2x EK Titan Block
1x XSPC Raystorm
6x Corsair SP120 HP
1x Bitfenix Hydro Fan Controller
5x XSPC male-female G1/4 thread extenders
12x XSPC Compression fittings
2 drops copper sulphate
12 square feet of acoustic damping foam
Primochill Red Pro LRT tubing
The top rad is crooked because I accidentally bought the multiport version, and nobody makes flush fitting plugs for it so it presses against the case ceiling. Plus the case was designed to support a 280mm rad MAX anyway lol.