Singer Vehicle Design has made a name with its lovingly conceived, elegantly executed Porsche 911 restorations in recent years. What started as a passion project has morphed into one of the most exciting operations in the motoring world – and now, it's teaming up with Williams Advanced Engineering and legendary engineer Hans Mezger to create the ultimate air-cooled 911 engine.

You might have heard Porsche fans speak about the Mezger engine with a certain degree of reverence. It refers to the water-cooled six that started off in Le Mans GT1 Prototypes from the early-1990s, before being developed and adapted for life in road-going 911 GT3 cars. Its reign came to an end in the 911 GT3 RS 4.0. Mezger has his fingerprints all over the flat six that debuted in the 1963 911, and he developed the flat-12 from the 917. As pedigree goes, his is a very good one.

The new Singer Vehicle Design engine will be a naturally aspirated, air-cooled flat-six with a 4.0L capacity. It will have four valves per cylinder and four camshafts, making a whopping 500 hp (373 kW) of power. The engine will be fitted to a 1990 911 owned by Scott Blattner, a long-time client of the company.

The finished product will have new cylinders and pistons with titanium con-rods, and its aluminum throttle bodies are paired with carbon fiber trumpets. Carbon fiber has also been used for the air-box, which has been tuned to deliver strong mid-range torque. Don't think this is all about low-down twist, though – redline should be somewhere north of that magical 9,000 rpm mark.

Lightweight materials like titanium, magnesium and carbon fiber have been applied lavishly in the new engine, which breathes through an Inconel and titanium exhaust. The initial list of upgrades is substantial, but expect to see even more when the car is completely finished. Suffice to say, it should be something seriously special.

"Helping our clients realize their unique vision for a reimagined Porsche 911 with the help of automotive royalty is very much a privilege," says Rob Dickinson, founder of Singer. "Singer is delighted to be working with Williams Advanced Engineering and Hans Mezger to offer our clients a 'next level' of restoration and modification services for their Porsche 911s. With careful and dedicated development, this iconic air-cooled engine has much to give both its existing devotees and a generation of new enthusiasts."

Each Singer is designed and developed for an individual owner. Check out our gallery for a look at some of these stunning re-imagined 911s.

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