By Tim Pitt Stonking V8 engines without electrical assistance have suddenly become an endangered species. Not long ago, all of Germany’s super saloons followed this recipe; now the BMW M5 has become a plug-in hybrid, while the Mercedes-AMG E63 has thundered off into the sunset, replaced by the E53 and its hybridised straight-six. Aside from the (largely forgotten) Audi RS7 Sportback, that makes the 2025 Porsche Panamera GTS something of an anomaly: a new car with an old-fashioned approach to going fast. If electric tech can boost horsepower and miles per gallon, though, surely that’s a good th…