Achleitner drops a clue that indicates the 911 hybrid will be a plug-in. He says that company simulations show a plug-in would add about 440-500 pounds to the overall weight, but simulations haven’t been done for a standard hybrid, which he estimates would add half as much weight.
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If Porsche were to develop a more potent motor than what’s in the Panamera hybrids and add it to the twin-turbo 3.0-liter flat-6 engine in the new Carrera S model, 600 horsepower could be within reach.

That’s a number that fits with Achleitner’s desire for the 911 hybrid to be a car “the customer goes into the showroom and says, ‘Wow, that’s a car I want to have.’” He also notes the hybrid’s performance must more than overcome the extra weight it adds. If not, Achleitner muses, he’d just take a C4S, which would be less expensive.