France's Tragic Stillborn - Citroën SM V8 Prototype

When ‘V8’ is mentioned in conversation, images of frighteningly quick drag cars and muscle cars are often conjured up. Whilst European and even some Asian manufacturers have had their respective slices of the neat 8-cylinder pie, the Americans and Australians tend to be famed most for their love of V8 powered automobiles. It may, then, come as a surprise to you, that the French tried to dabble in this unfamiliar game, by whipping up a more exciting, faster version of a preexisting model which was only ever used as a test mule. It’s Frankenstein’s beret-wearing cousin.

The conflicting tale started in the early 1970s, during Citroën’s time of working with Maserati and during the oil crisis. As the crisis was in full swing, less and less people were buying the flagship SM model due to the skyward-bound fuel prices. In a tangled turn of events, Citroën decided a more powerful engine for both companies’ flagships was needed, and with the new Maserati Quattroporte around the corner it seemed like the perfect decision to work on a powerplant with more power. Maserati, as the company under Citroën’s control, were forced to take the reins. The 2.7 litre and 3.0 litre V6s previously used just weren’t really up to the task of moving the weight granted by an extra set of doors. The engine was derived from the 3.0 V6, though saw the addition of two more cylinders from another example of the same engine. Displacement rose to 4.0 litres, more precisely 3953cc.

This fantastic new creation was all well and good, but before Maserati could justifiably plonk it in their big saloon, they had to test it to see what the engine was like to live with. As it shared its underpinnigs with the Citroën SM, the natural candidate to test out the engine was the big French coupé. Between 11,000 and 12,000 miles (no exact number was recorded) of testing was performed and the engine sailed by faultlessly. The engine was, whilst in theory just two engines shunted together, plenty powerful and capable of making the SM as sporty as any contemporary. Power was up from 210 in the 3.0 to 270-280 in the new V8 and a surge of torque followed suite. Alongside the much-needed power boost came tweaks to the hydropneumatic suspension system. The pressure was increased to stiffen the ride, limiting bodyroll and thus improving the car’s handling.

Bankruptcy unfortunately hit the companies hard in 1975 and they parted ways, with the new De Tomaso ownership cancelling the V8 project and having the SM crushed, though the 4.0 V8 engine was kept in storage. The Quattroporte II was produced with the gutless old 3.0 V6, and very nearly didn’t sell at all. Production was ended after just 13 were built across the span of 2 years. In 2009, Maserati sold the engine and after exchanging ownership a number of times, fell into the hands of Philip Kantor. He, an enthusiast himself, bought the engine as a tribute of sorts to his (then) recently deceased father who had been a big fan of the SM model. He had the engine fitted to a near-identical SM (even in the same colour, Rio red) where it sits to this day.

What this car represents is a classic case of a manufacturer biting off more than it can chew. A larger, more powerful engine was simply not needed during the time period, and without a good enough backbone product to keep profits ticking over, the companies at the forefront of the project went under and had to throw the towel in. The engine went for a long time unused, though now sees service in a functional road vehicle, a tribute to a humble test mule which, under better circumstances, could have paved the way for Citroëns of the future.