Abstract: A process of converting high molecular hydrocarbon feedstock into lower molecular weight components in the presence of a homogenous catalysis system is disclosed. The catalysis system comprises a catalyst complex formed by the interaction of a metal halide-type Lewis acid, a protic Bronsted acid or Bronsted acid donor and a fluid hydrocarbon selected from a C.sub.2 -C.sub.14 alkane dissolved in a fluid hydrocarbon. The homogeneous catalysis system can be produced as a liquid phase or a supercritical fluid solution. The process is especially useful where the hydrocarbon feedstock consists of deasphalted oil or mixed paraffins. The hydrocrackate, especially that derived from paraffin feedstocks, has a carbon number distribution equivalent to that of the fluid hydrocarbon of the catalyst complex.