The automotive gas turbine has not been adopted for many reasons, among which are that the materials required have been expensive, and the fuel consumption has been unremarkable. A new approach is to use a marked reduction in blade speeds (and therefore in blade and disk stresses) through multistaging, allowing the use of injection-molded compressor components and low-cost ceramic materials (e.g. technology developed for automotive turbochargers) for all hot parts. The pressure ratio will also be lowered and the heat-exchanger effectiveness increased. The resulting engine is larger than existing experimental turbines but still smaller and lighter than an equivalent spark-ignition or compression-ignition engine, with a marked improvement in projected fuel efficiency.