This car has a 700-plus horsepower, 5,500-cc twin-turbocharged dual overhead camshaft V12 engine, 6-speed sequential manual paddle-shift gearbox, independent front and rear double-wishbone suspension, and four-wheel hydraulic ventilated disc brakes. The wheelbase is 116 inches.

• 2009 Le Mans Works entry
• Exceptional and undisputed racing provenance
• 1st Overall at Monza, Silverstone and Spa
• Groundbreaking HDi diesel-powered V12 engine
• Run by the Works-Peugeot factory race team
• The first Peugeot 908 HDi to ever be offered for public sale
• Rare and important milestone in motorsports history

SCM Analysis


Vehicle:2007 Peugeot 908 V12 HDi FAP Le Mans Racer
Number Produced:6
Original List Price:N/A
SCM Valuation:$1,700,000 to $2,000,000
Chassis Number Location:Unknown
Engine Number Location:Unknown
Club Info:Historic Sportscar Racing Ltd.
Alternatives:1978 Rondeau LM GTP, 2002 Cadillac Le Mans prototype, 1984 Porsche 962

This car, Lot 382, sold for $2,175,600, including buyer’s premium, at RM’s Monaco auction on May 12, 2012.

When I was a younger man, the idea of conflating terms such as “diesel” and “race car” was considered an oxymoron along the lines of “reliable English car,” “exciting Mercedes” or “affordable Ferrari.” They just weren’t terms that anyone seriously considered using in the same sentence.

Diesels were heavy, slow, smoky, dull — did I mention slow? A joke running around West Los Angeles during the mid-1970s maintained there was a new driving school established to teach people how to drive the Mercedes diesels that were becoming popular. To provide an authentic learning experience, the school cars were overloaded Chevy 6-cylinder automatics with the emergency brake half set.

The school was a joke, but the performance problem was really true; I recall getting my first ride in the new 300SD turbocharged Mercedes and being astonished at the acceleration, even though in retrospect it wasn’t any faster than a 280S. It was just so much more than I expected. The traditional racing-car values of lightness, balance, responsiveness and high power to weight just weren’t accessible in those days with diesel power.

No longer just tractor pushers

Time rumbles forward, though, and the 40-year span between then and now is chronologically identical but technologically eons greater than the equivalent span from the mid-1930s to the mid-1970s. There were three grand impediments to making diesels the light, responsive, powerful units that racing requires: 

1. The design technology to build a lightweight block structure to carry the immense loads generated by the diesel concept.
2. The development of responsive automobile-sized turbochargers to cram the air into the engine.
3. Finally — and most importantly — effective, real-time fuel management.

To understand the accomplishment of a serious diesel racing car, we need to spend a bit of time with each of these challenges.

Building a strong, light block

The fundamental structural problem with the diesel concept is that it puts immensely greater loads on the system than an Otto-cycle (gasoline) engine does. The gas engine mixes fuel and air, compresses it and lights it on fire, where it burns (very quickly, but it never explodes) and the resulting gases push the pistons down.

If it the gasoline-saturated vapor explodes, we call it “detonation,” and the shock loads will tear an engine apart in seconds.

A diesel, on the other hand, plans on detonating all day long. The idea is to compress the air so much (22:1 is a sort of normal static compression ratio, then add supercharging) that it heats itself, then squirt fuel in at the top of the stroke, where it literally does explode, at least at the beginning of each power stroke, which is why they’re noisy. The loads that this puts on the rods, crankshaft, and bearings are spectacular and require a very strong system (remember when GM tried to convert their gas V8 into a diesel in the ’70s? it didn’t even come close).

In the beginning, manufacturers solved this problem by literally pouring great masses of cast iron at the problem, which worked as long as you didn’t care about weight. As part of the digital revolution beginning in the 1970s, computer technology developed to the point that internal load patterns could be parsed out and CAM machines could cut away the non-essential metal. This, combined with a concurrent revolution in which precision die casting replaced sand casting as the way to build the core blocks, allowed huge amounts of weight to be removed from engines without compromising strength. It also eventually allowed for aluminum diesel blocks for racing purposes — although they’ve never been practical for production cars.

Under pressure

Today we take turbochargers for granted, but the small, responsive ones suitable for automobiles — and particularly race cars — have been around for only a few decades. The ability to cram a lot of air into a cylinder on short notice is essential if you are going to get the power needed to be competitive. It is important to remember here that diesels do not use throttle or induction restriction of any sort, as the speed and power are determined solely by how much fuel is squirted in and whether there is enough oxygen to burn it.

The biggest development by far was the development of what is generally called “common rail” diesel fuel injection. In a diesel, the fuel is squirted directly into the cylinder at the worst possible time (highest cylinder pressure), which means that it has to come out under extremely high pressure to spray out and burn correctly.

Traditionally this was accomplished with a timed mechanical pump, which is a set of variable displacement pistons, each pushing a certain amount of fuel (quantity determined strictly by throttle position) through a pipe to a nozzle in the appropriate combustion chamber. There is nothing wrong with this, but it is not subtle, efficient or responsive.

The idea of common rail is that it uses a single, pressurized fuel galley for all the cylinders (a “common rail”) and uses computer-controlled, electrically triggered injectors to dispense the individual fuel pulse. This is essentially exactly the same as the fuel injection in your Bimmer or Cadillac, and it allows real-time management of every pulse of fuel. The system considers throttle opening, change in throttle, amount of air available, temperature, engine load, and who knows what else. All this allows extraordinary precision in optimizing fuel burn.

The catch for diesels is that the pressures are so great, that what seems an easy concept becomes an immense challenge. Your port-injected BMW runs gas at about 60 psi, but our Peugeot race car calls for 15,000 psi diesel fuel pushed through a micro-electronically fired injector for durations of roughly 1/100th of a second about 36 times a second (at 4,500 rpm), and that with precision timing and spray pattern so it burns right.

This becomes a pretty spectacular problem with strange complications. Some years ago, a Mercedes engineer told me they were having problems with the fuel being pushed up the injector trigger wires, between the wire and the insulation, and flooding out the electronic control boxes.

The point, of course, is that they did figure it all out, with the result that a modern diesel street car is almost indistinguishable from its gas-powered equivalent in anything except fuel efficiency and purchase price — both are significantly higher. The manufacturers, having invested staggering amounts of time and money developing what they felt to be a truly superior product, had to face the next problem: how to sell it.

On the tracks — and the auction block

Endurance racing would seem to be an obvious solution to the marketing issue of trying to change diesel’s image in the minds of consumers, but in the end only Audi and Peugeot chose to go that route. The various rally authorities proved very responsive and allowed the rules to be adjusted to not-so-subtly allow advantages to the new concept — at least while it established itself. I can imagine how many times the meetings about rules were punctuated by “but it’s a diesel!” as Peugeot and Audi worked this out. They were successful, though, and both Audi and Peugeot won Le Mans and other important races. So, the idea of a world-beating racing diesel is no longer an oxymoron.

So what are we to think of the subject Peugeot 908, and particularly, how should it be valued? There isn’t much in the way of comps to be found.

I know of at least one diesel R10 Audi and several R8 (gasoline) cars that run the Eastern United States, but they were apparently privately purchased. This is the only 908 Peugeot to have been released (it was sold by the factory), so the waterfront is pretty short when it comes to covering the options.

It is definitely a very cool car and, I’m told, fun — but a bit boring — to drive. It is way fast, and air-conditioned to boot (per the rules for closed cars). Plus, there has to be a huge FOB (First On Block) factor in play in the value. If you want the only one of something special, you have to be willing to step up when the opportunity presents, and clearly there was more than one bidder willing. I would say this was an expensive but not irrational purchase by a knowledgeable buyer; well sold — and fairly bought.

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