That's a resounding yes, using the technique for braiding a straight 4-strand challah described above. Like with the adaptation for a 6-strand challah, with an 8-strand challah when you place the strand in the middle, you will have 3 strands on either side instead of 1. For a different look, you can also use my instructions for braiding an 8-strand challah as demonstrated on The Great British Bake Off (aka The Great British Baking Show).