In Mazda RX-8 you get 290 liters of free space in the trunk. You also may put the back seat of RX-8 down to receive more space than 290 liters. The figure was formed by Mazda during designing the 2004 year models. You may always put small shopping things in RX-8 trunk. The shape of Mazda’s trunk is quite appropriate.
Check also if your luggage in 2008 Mazda isn’t heavier than needed. The number of 290 liters cargo space is provided by Mazda and is appropriate for vehicle. Overloading Mazda RX-8 might be a great problem in future.