Yahoo Autos How Porsche Adapted the 918 Spyder Engine for the New 963 GTP Hypercar
The last time a V8 powered a Porsche prototype race car was nearly two decades ago in the RS Spyder that competed in the American Le Mans Series (ALMS) LMP2 class. The LMP2 car may have experienced some growing pains at first, but overall it was incredibly successful, winning the championship title every year it ran in the series, from 2006 to 2008. When it came time for Porsche and Penske Motorsport to return to the next-generation Prototype class in both IMSA and WEC, it was only natural for the team to borrow from its winning roots. The V8 engine in the 963 you’ll see on track this weekend at the Rolex 24 at Daytona has a direct connection to the Porsche V8 that dominated ALMS — and powered the road-going 918 Spyder hypercar.
From LMP2 to 918 to 963
“7 and 7": On the left, the 2023 Porsche 963 LMDh car. On the right, Porsche’s winning LMP2 prototype competitor for the ALMS series.
Jalopnik sat down with Thomas Laudenbach, VP of Porsche Motorsports, at IMSA’s final test for the Prototype class in December. Laudenbach was in charge of the engine department for Porsche and Penske Motorsport’s LMP2 efforts in the mid-2000s. The 3.4-liter V8 that powered those winning cars provided the basis for the 4.6-liter twin-turbo V8 in the new 963.
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“Obviously, at that time it was a smaller cubic capacity, but it’s the same architecture,” Laudenbach told Jalopnik. But the 3.4-liter would go through another evolution before making it into the 963.
For the 2023 IMSA season, Porsche needed an engine that would work with the mandatory hybrid system shared by all GTP hypercar competitors. Luckily, the automaker already had experience building car that paired a hybrid system with a V8. “If you go into a series that is driven by controlling costs, you think about what we have in-house,” Laudenbach said. “Basically it was just putting it on the table and asking, why shouldn’t we use the 918 Spyder as a basis?”
The 918 did, in fact, utilize the LMP2’s V8 architecture. However, the road-going car required modifications to meet emissions regulations and other legal requirements that differed from racing. The mid-engine plug-in hybrid used a naturally aspirated 4.6-liter V8 producing 608 hp, with an additional 286 hp supplied via the two electric motors at the front and rear of the car.
The Answer is Always V8
The 963's V8 twin-turbo engine neatly fit into the rear of the car.
In a field with Cadillac’s hearty naturally aspirated V8 and Acura’s twin-turbocharged V6, Porsche split the difference with its twin-turbo V8. The decision to use a V8 came down to what Porsche engineers decided would fit best in the spec hypercar. “The engine carries the load of the rear axle,” Laudenbach said. “So, we needed a structural engine. And then you’ve got to decide the number of cylinders — and there was no reason to go to six. There was no reason to do anything different.” While a six-cylinder engine would have meant less internal friction, Laudenbach explained that since the position of the rear wheels (and thus the transaxle) was fixed, a six-cylinder would require a long spacer to mate to the gearbox.
