Titan X SLI Cooling Ideas?

I've packed two Titan X's into an H440, finished a custom water cooling loop throughout the system, and attached four Noctua fans to the radiators but the cards seem to still be running a little hotter on average than I would like. After looking into other ways to cool them, I'm still not too confident on my ability to cool two extremely high end cards in any exotic way.

Since I've heavily modified the case, I can't add many more wide parts. I can remove LED's if needed and up to two fans if any efficient enough cooling options are suggested. Up to three more fans can be added with a bit more moving but not if they wine at low speeds. Any ideas?

Many thanks,

How many radiators are in your loop?
You can accomodate 140.2/120.3 front & top + 140.1/120.1 @ rear. 3 good radiators should cool 2xgpu + cpu.
If you've got just say 120.2 (240mm) trying to cool 2x gpu + (possible but not stated) a cpu then you have to expect high temps.

There's currently three triple 120mm radiators cooling both Titan's and a Xeon E5-2697. I did notice a very, very slight kink in the loop just a few minutes ago. I don't know if it was bad enough to cause cooling issues but I'm running a few tests to find out.

Thanks for the insight.

3 x 120.3 rads - is one mounted externally?
Either way just over 1 sq mtr of cooling surface area should be heaps.
What are the temps -idle, load, ambient?

3 x 120.3 rads - mounted externally
thats what i have
and im only cooling an i5 2500k with a gtx 970