About bisque firing raku pieces? Please help me out?

I have bisqued raku quite a while ago, so I know it is possible. I think it took about 5 hours, the process is much longer than the final raku firing. You slowly turn the gas/temperature up in a couple of steps. Be particularly careful at the beginning, for that is when water which may still be left in the clay can evaporate (it shouldn't turn suddenly to steam). Bisque firing is usually done between cone 08-04, so if you have a pyrometric cone you could check the temperature. Sorry, I don't remember more details. But you could check some pottery discussion groups or ask a questions at one if they can give you a better schedule. But as it ultimately will depend on the specific design of your kiln I would expect that the best way to find out would be to fire some test pieces.