The right way for Tata to make a Rover hybrid is a small diesel power plant (45 hp) powering 4 electric motors in the hubs, like a diesel train. You could run the diesel at what ever its most efficient rpm is and with hub mounted motors you would get crazy low end torque. Alas, it will be some over heavy pos that gets slightly better mileage then the standard model.
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And you would't have any axles to deal with. Crazy ground clearance.