The engineers at German supercar motor house, Porsche, have applied some knowledge that has actually been part of conventional wisdom amongst drag racers and extreme vehicle tuners for some time: any power problem can be solved by adding a turbocharger – or three.
The engine in question is not even a fringe development lump from a race car, but the seminal 911 Turbo’s pressure-aspirated flat six, suggesting that the development team is very confident of its plans.
The reason for the addition of a third turbocharger is not to produce more power, but to smooth out the power delivery at lower revs while limiting the adverse effects of turbo lag (the time it takes the turbocharger to spool up before it can add its power).
Big turbochargers suffer from more lag, while smaller units are far less susceptible. This has resulted in the development of hybrid turbocharger configurations, where a small turbocharger is placed in front of a larger one.
With the addition of a third turbo, Porsche has shuffled around the configuration of the forced induction units, applying a smaller turbocharger very close to the engine, with the two bigger units mounted in a similar fashion to the 997-generation 911 Turbo’s engine.
The food-for-thought here is that Porsche has always used variable-geometry turbochargers, which also limit the effects of turbo-lag, so we would hypothesise that the third in-line turbocharger is meant to reduce the fuel consumption and CO2 emissions coughed up by the 911.
It’s not that the turbocharger makes the engine run cleaner, but rather that it allows the driver to drive more efficiently.
There is likely to be a power hike in the new 911 Turbo engine, but we suspect that it is purely an expression of fan service. It would hardly be good news if the power output remained unchanged, despite the addition of a third turbocharger. Instead, the new engine is expected to touch the 390 kW mark, and should be impressively tractable, making it easier than ever to control all those horses.
The new 911 Turbo is due next year, but a preview model is expected to debut at the Paris Motor Show in October this year.
