I'd say go ahead and make it a 4 day split. I've seen much better results in the last month, when I went to a 4 from a 3. This is simply because I have a more limited amount of time to do each workout than I used to. Each day takes 30-45 minutes or less.
Mine looks like:
Day 1: Chest
Day 2: Back/Biceps
Day 3: Legs
Day 4: Shoulders/Triceps
A good 3 day split could be
Day 1: Chest/Tri's
Day 2: Back/Bi's
Day 3: Legs/Shoulders
Most people say to not work anything with legs, but do what you gotta do.