The straight Skinny....YES [img]/ubbthreads/images/graemlins/smile.gif[/img] you can. And NO you can't [img]/ubbthreads/images/graemlins/frown.gif[/img]. There are only 2 things you need to know about SVO/WVO. First it needs to be Thinned out, and second it needs to be filtered.
EVERYTHING else revolves around how to do just that. Some people heat it to thin it enough to use, some process it into BIO, and some simply mix it with #2. Because it becomes a solid at roughly 25-40 degrees(depending on quality, type and use of oil) You can not live in North Dakota in the winter and just pour it in your tank and go. If you live in Kuwait, where it doesn't get below 100 during the summer[img]/ubbthreads/images/graemlins/crazy.gif[/img], you could get away with it. Several, including myself have mixed it with #2 in ratios up to about 75% WVO to 25% diesel with no problems in the factory unheated tank. But only if you are in a warm environment, meaning doesn't get much below about 65-70. And you will need to carry a spare fuel filter. The colder your climate, the more diesel you need to add to the ratio.
Several of us have gone through the effort of installing a second heated fuel system just for WVO so climate and seasons are not an issue. Just pour and drive. There is a lot to take in when getting into this, unfortunately there is no quick easy answer. But this is a great place with great people. And you will learn much.
Journey To Forever has a lot of great information on Biodiesel and WVO as fuel.