McLaren’s M840T V8 engine has already been raced by Nissan at Le Mans

McLaren’s 720S is arguably the definitive modern supercar of our time. One of the features that elevates it above the competition is its engine – a 4.0-liter twin-turbo, hand-cranked V8 developing 530kW and 770Nm.

Dubbed the M840T, the device is an absolute monster, with seemingly endless reserves of power that it deploys without prejudice.

Despite its all-encompassing charisma, the M840T remains a cohesive part of the 720S package – something we discover with every practice as MOTOR has Woking’s Super Series monster in our long-term test fleet.

But there’s another story to be told with the M840T, which forgoes the intricacies of throttle calibration and torque curves for the pages of history books and gives unique insight into how engines can have a line as complex as a royal line.

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It’s the story of how racing cars from Le Mans and a Japanese automotive giant gave birth to McLaren’s family of modern supercars.

The first thing to recognize is that McLaren doesn’t actually build the M840T itself (much like the iconic naturally aspirated V12 that sits amidships in the original F1). Instead, British firm Ricardo is responsible for building the M840T, shipping completed units to McLaren headquarters in Woking to be put into cars. That said, the Woking team holds as much ownership over the finished product as if they had assembled it themselves.

This is the beginning of the rabbit hole. Take the red pill and you’ll find that the bones of the M840T are older than the McLaren F1 road car.

To explain how, we have to go back in time to 1987, when Nissan began work on an all-new engine designed exclusively for motorsport use, namely the mega-powerful Group C regulation used in global car competition. sport.

Nissan R390V8

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Nissan wanted a bespoke unit to propel its Group C driver to 24 Hours of Le Mans glory (which sadly never became a reality).

Yoshikazu Ishikawa designed a 2996cc twin-turbocharged 90-degree V8 with an 85mm bore and 66mm stroke. The resulting engine was dubbed VEJ30 and fitted to the R87E racing car. Still with us?

Unfortunately for Nissan and Ishikawa-san, the VEJ30 failed to deliver the expected results.

Enter Yoshimasa Hayashi – a longtime NISMO employee who shares his name with Japan’s current foreign minister. Hayashi-san took the VEJ30 and made a number of changes, including increasing the displacement to 3.4 liters.

Nissan R 390 Pit

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The reworked engine was later named VRH30 and used for Nissan’s 1988 campaign. Again, the results were deemed insufficient.

For 1989, another all-new engine project was launched, with development examples fitted to the R89C Group C racer. The fundamental ingredients remained, but eventually Nissan engineers built something to live up to their expectations: the VRH35.

It was what would eventually, after two decades and an entirely different Le Mans prototype program from Nissan, be used by McLaren as the heart of its second creation, the MP4-12C.

The leap from Group C to road car is considerable, even for vehicles as fast as a McLaren.

Nissan R 390 GT 1 66

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Closing the gap is the R390, a GT1 machine built by Nissan to race in the 24 Hours of Le Mans under the aforementioned GT1 regulations.

We won’t go into too much detail, but the R390 itself was something of a redesigned XJR-15, both sharing the same designer in Tony Southgate, and were run by Tom Walkinshaw Racing.

GT1 regulations in the late 20th century required road-legal versions of racing cars to be built and sold to the public. It was an open secret that manufacturers competing in GT1 drove double-decker buses through various loopholes that regulated this part of the rules, but appearances had to be kept.

To appease the powers that be, Nissan built a red prototype version of what it planned to sell to the public. This was then repainted and given an all new VIN to become the blue “long tail” road version that many have known from its time in Gran Turismo racing games.

Nissan R 390 road car

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Nissan never sold a single R390 road car. To this day, it remains conjecture if he ever actually intended to do so. We’re not going to delve into this convoluted maelstrom of speculation, but what’s important is that the VRH35L never hit the road.

After the R390 project was completed, the VRH35L was put on a shelf to collect dust. Yes, other VRH engines were built by Nissan, but the twin-turbo king was on an indefinite nap.

That was until the late 2000s when McLaren started looking for suitable engines to power their first road car, the MP4-12C. McLaren built its reputation as an engineering company, but didn’t quite have the capacity to support a fully bespoke engine alongside its chassis development duties.

A modified VRH35L was developed and placed in a very early development mule built from a Ferrari 360. By this point the Nissan engine capacity had increased to 3.8 litres, with legendary companies Ricardo and Ilmor both having their fingerprints on the project.

Nissan R 390 GT 1 3

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When McLaren finalized that it would go with the twin-turbo V8 design, it bought the rights to the VRH35L engine wholesale from Tom Walkinshaw Racing. After carrying out extensive work on the engine alongside its engineering partners, McLaren then renamed it M838T.

This engine was used in the MP4-12C, 650S, 675LT, P1, 540C, 570S and 600LT, before a series of further changes increased the displacement to 4.0 litres, bringing a new name (but the same fundamental design) in the M840T. McLaren claims that 41% of the M840T components are new compared to the M838T.

Other than the block’s center bones and 85mm bore diameter, almost nothing remains of Nissan’s VRH35L in the M840T. However, it’s confusing at best to describe either Woking unit as “brand new” given their lineage. Engines from Nissan and McLaren have both developed a worthy heritage.

This twisted mechanical story creates an intriguing historical paradox, where McLaren’s most powerful modern road car engine competed against the F1 GTR and its 6.0-litre S70 V12 sourced from BMW at Le Mans in 1997 and 1998. Sometimes, history can be stranger than fiction.

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