Shutter priority and AF-C modes, most definitely. With the movement, aperture shouldn't be too big of a concern since the movement blur will add to whatever normal depth of field blur there is or isn't.
Which speed depends a lot on focal length, with wide angles not showing nearly as much movement. You want to pick a shutter speed that allows you to get the background blur while being reasonably fast enough to allow a crisp capture of the thing moving. Since 1/focal length is the standing rule for stopping casual movement then figure that if you are sweeping through the frame then 1/focal length should serve as your starting point for where blur will happen with conscious movement. Start there and then move to slower speeds.
What exactly your best speed is depends on both the speed of the thing moving and your ability to maintain the subject in a fixed spot in the frame. The faster it's moving, and the longer the focal length, the faster you can shoot and still get background blur. If this is your first shot at it, start with the 1/focal length speed and then move down in one click intervals to see what works best for you. The better you get at sweeping through the shot with the subject the slower you'll be able to go, and the slower the speed the more blur.
Oh, and shoot in Continuous High mode, if you hadn't already planned on that. In any given 1-2 second sweep if you nail 1/2 your frames you did alright. And if you're talking about race cars or cyclists, you may be able to go even faster than 1/focal length and get blur.