The Porsche V8 is now well into it’s fourth decade on earth. First unveiled as the engineer to power the supposed 911 replacement – the Porsche 928 – back in 1977, a V8 was a logical choice for Porsche. A larger displacement V8 allowed Porsche engineers to detune the compression ratio of the engine, allowing the engine to run on a full variety of fuel grades; a crucial move to enable Porsche’s newest sports car to be a worldwide success.
That 46 year old V8 seems a little quaint now, with 16 valves and only a single camshaft per cylinder bank, although displacement was respectable at 4.5 Litres. Say what you will about Porsche’s evolutionary-rather-than-revolutionary approach to engineering, but as so often with Porsche projects, this V8 was an investment for the future. The 928 stuck around being far longer than Porsche had intended – particularly as the car was a sort of direct rival to the famous 911 – mainly due to its enigmatic design.
In 1986, about halfway through the 928’s lifespan, Porsche created a heavily revised V8 engine. Still a 90 degree V8, the new engine boasted dual overhead camshafts and four valves per cylinder. By the time the 928 bowed out in 1995, the top of the line 928 boasted a 5.4 Litre V8, which for a European car, was and is still impressive.
The 1990s for Porsche was a time of uncertainty and a lot of sucking of air through clenched German teeth. As the millennium ticked over, Porsche now had two models, the 911 and the Boxster, and thanks to an arse-kicking in production sense from Toyota, the company was again on stable footing. In 2002 along comes the Porsche Cayenne – an SUV sent from the heavens to fill Porsche coffers (although it was styled in hell) – and under the Cayenne’s bonnet was the second generation Porsche V8.
Early Cayenne V8s matched the displacement of their 1977 forbearer at 4.5 Litres, but the engine used in the more pokey Cayenne Turbo and Turbo S models embraced one of the definitive high-performance engine configurations: take a venerable V8 and mount twin-turbochargers. The first-gen Cayenne Turbo S had a peak power of 521bhp, making it Porsche’s second most powerful production car at the time.
After this the Porsche V8 was pulled in two distinctly different directions. The first was more of the same from the Cayenne. The second-gen Cayenne and newly introduced Panamera used 4.8 Litre naturally-aspirated and twin-turbocharged versions of the second generation engine. The latest Cayenne and Panamera now use a heavily revised 4.0 Litre twin-turbocharged variant that, at its most potent, makes 660bhp in the latest Porsche Cayenne Turbo GT.
The other direction the Porsche V8 was taken towards was the one thing that draws Porsche resources and brain-power like nothing else: motorsport.
This racing V8 was not at-all related to the Porsche V8s of yore. Debuting under the sleek bodywork of the Porsche RS Spyder LMP2 car in 2005, this new V8 was a small-displacement 3.4 Litre masterpiece. Boasting a flat-plane crank, this new engine revved past 10,000 rpm and was pivotal in making the Porsche RS Spyder the dominant LMP2 racing car. In fact, the Porsche RS Spyder was so fast it took both first and second place at the 2008 12 Hours of Sebring, beating the all-conquering Audi R10 TDI LMP1 whilst it was at the height of its powers.
Rule changes in 2011 made the RS Spyder redundant, but again this engine was an investment. Perhaps for a racing engine, long-term investment is not quite the name of the game, and instead Porsche engineers thought: “oh bugger, here’s this engine we’ve spent millions and millions of Euros developing and now it’s useless,” but Porsche being Porsche, found a way out.
The 4.6 Litre V8 used in the 918 was a direct relative to the 3.4 Litre racing V8 used in the RS Spyder. Featuring 32 valves, a dry sump, and a heady redline, the 918’s V8 was a the time the highest specific output engine in a production car with 599 bhp which translated to 132 bhp per litre.
The 918 is no more, and it looked for a long time that the Porsche V8 would be hanging up its racing overalls and return to duty powering numerous Cayennes and Panameras, but that was not the end.
Porsche’s newest top-flight endurance racer – the 963 – uses a 4.6 Litre twin-turbocharged V8, again a derivative from the RS Spyder and 918.
Will the 963 become a dominant Porsche endurance racer like the RS Spyder before it? Only time will tell. I’m just happy to see the old-dog has some life in it yet.
Kerbside 