Yea it will be able to SLI. Each card will rum at x8 speed only since the 6800k only has 28 lanes.not enough for x16 each. So it will be slightly slower than a 40 lane CPU could provide. However, the 6850k, 200$ more, has 40 lanes and will run each card at 16x, but for that, it is not worth it. So stick with the 6800k.
Thanks a lot Ryan! I will stick with the i7-6800K and save $200