Hennessey gonna Hennessey.
It feels like the holidays arrive faster than ever before. Texas-based builder and tuner, Hennessey, has a long tradition of attaching a Christmas tree on top of an engine to test its speed. This year, Hennessey did this by strapping the tree to the roof a tuned Porsche 911 Turbo S. John Hennessey has his personal Porsche 911 Turbo S .
We don’t know much about the tuned Turbo S, but we do know that it produces 750 horsepower (559kilowatts), which makes it a significant improvement over the stock 641 HP (477 kW). With the tree attached to the roof, it’s enough power to propel the coupe to a stunning 175 mph (281 km/h). Although it’s impressive, it’s still far below the car’s top speed. The second lap around the Pennzoil proving grounds of the tuner’s Pennzoil motor reached 206 mph (331 km/h). This is a difference of 30 mph. Spencer Geswein, a racing driver, piloted the Porsche. In the video, he says that the Porsche felt completely different after removing the tree. The aerodynamically unfriendly tree was removed, and the car behaved differently at high speeds. This is not surprising. A roof that is so large at such speeds can have a profound impact on how the car feels and works.
Although the Porsche’s top speed of 175 mph is impressive, it is not Hennessey’s fastest Christmas tree. The Hennessey-tuned Jeep Grand Cherokee Trackhawk snatched the title. It used all 1,000 horsepower to reach 181 mph (291 km/h), which is the SUV’s top speed. It didn’t have to drag as much because of its flat nose. The Jeep’s Hellcat V8 tuned to maximum power easily overcome the tree’s drag.