Porsche produces all of their 911 Turbo engine blocks out of aluminum. The 997.2 generation switched to aluminum from the classic GT1 (Mezger) iron block and it is aluminum used ever since. That makes the block lighter but as boost and cylinder pressure increase with Porsche upping the power block integrity eventually becomes an issue. We see stock internal Porsche 991 Turbo 3.8 blocks holding up to lots of power but Porsche durability testing and aftermarket testing are different things. Not to mention, Porsche knows there is a segment that buys the 911 Turbo to modify it and to keep up with the big boys the Turbo will need to be able to take abuse. Porsche is increasing 992 Turbo S horsepower to ~650 stock and that figure is probably underrated. They are doing this with a revised intake, manifolds, intercooler, and larger VTG turbochargers. The bigger turbos will push more air. The 991.1 Turbo and Turbo S shared the same VTG's and struggled to top the 997.2 in bolt on performance. The 997.2 Turbo S did run 9's with bolt ons. The 992 Turbo S will be the strongest bolt on tuned Porsche Turbo yet on the factory turbochargers. We might see a high 9.X in the 1/4 mile out of it stock meaning it is going to go deep into the 9's tuned. With the new 8-speed PDK (it will share the Carrera S ratios but with a different final drive) the car is going to be a monster out of the hole. The PDK is more compact but heavier than the 7-speed it replaces so it sounds like Porsche made sure it is beefed up for 992 Turbo duty. The front differential is also watercooled and strengthened: All signs point to a driveline reinforced to take a serious beating and Porsche would not add iron liners at additional cost just for fun. The 992 Turbo should be epic.