“It’s a modified Speedster engine,” confirms Porsche’s GT line director Andreas Preuninger. There are differences, because the 992-generation 911 GT3 will have to pass regulations not applicable to the 911 Speedster during its production cycle, but the 4.0-litre naturally aspirated flat six revs to the same glorious 9000rpm.
The output? Preuninger’s saying 503bhp, so the same as the Speedster, and an increase over the previous 991.2 GT3’s 493bhp.
Not a huge bump in power, then, but homologating what’s essentially a racing engine for the road isn’t the work of a moment, especially given ever-stricter regulations around emissions, particulates and sound. They’re so restrictive these days that Preuninger says some 80% of his team’s engineering time is applied just to maintaining the GT3’s level of performance, which leaves the remaining 20% of their efforts for improving it.
The gains this new GT3 will bring are generated elsewhere. Preuninger’s quick to point out, though, that there won’t be any more weight, saying: “I didn’t want the car to be heavier. That was critical. It has to be bigger because I've got the 992 body now, but I don't want to carry more weight.”
Using the usual GT3 mass-reduction route - no rear seats, less sound deadening, lighter materials, thinner glass and, now, a carbonfibre bonnet - the 992 GT3 weighs no more than its predecessor. That’s been achieved without resorting to things like deleting the air-con – which isn’t even possible with the new 992 GT3.
We’re in one of Porsche’s many prototypes and Preuninger is driving on familiar roads around Weissach. He says: “This is a Motorsport car so it has to live up to that expectation.” There’ll be a lap time applied to it when it’s launched, but for now, he’s saying nothing, except, obviously, it’ll be quicker. The improvements, then, are centred around the GT3’s chassis and aerodynamics, with significant changes throughout.
The most obvious visual clue is the aero and, in particular, the rear wing. “It's always form follows function – always, especially here,” he says. The wing apes that of its racing relations, being hung-mounted, creating beneficial, uninterrupted, airflow under it. Usefully, too, it cleans up airflow into the GT3’s engine. There’s a huge diffuser out back as well, a flat underside and airflow-managing and exploiting ducts in the front and underneath – all doing everything they can to force the rushing air to do the job that the GT department wants from it.
It has worked, convincingly, and this GT3 comes with a 50% increase in downforce but without any increase in drag. That’s significant, not just for track speed, but because Preuninger wants the GT3 to be quick at high velocities. “We live in Germany with autobahns and I want it to accelerate heavily until you see a 'three' as the first of the triple digits. After that I don’t care,” he says.