An exhaust processor assembly is provided for processing a flow of combustion product supplied by a source. The processor assembly has a housing including an inlet coupled to the source for admitting combustion product into the housing. The inlet includes first and second diverging nozzles interconnected by a transition section of uniform cross-section. A diverter is positioned in the inlet for interrupting the flow of combustion product traveling through the inlet toward the substrate. The specially configured inlet and the diverter cooperate to substantially uniformly distribute the flow of combustion product introduced into the housing across the inlet face of the substrate. Such uniform distribution provides a distributed exhaust flow designed to load the substrate substantially evenly to enhance combustion product treatment efficiency of the substrate means.