Foamy oil solution gas drive mechanisms are complex and our knowledge and understanding is limited despite the extensive studies in the literature. In order to advance our understanding of heavy oil solution gas drive mechanisms, long core depletion experiments were designed. These experiments were performed on sand-filled or glass beadsfilled tubes that are x-ray transparent and have pressure transducers along their length. The novelty of the experiments is the length (of over 18 m) that they extend and the duration of the experimental runs. The results of the longer experiments should be able to provide data that bridge the gap between the field scale and the shorter laboratory experiments that have been performed in the past. Thus production, pressure transient, and saturation data are presented in this "extended" scale. In addition, CT scanner images are expected to provide information about the evolution of gas.