The biggest crowd puller at this year’s Retromobile was an impressive display of intriguing rhomboid cars, these being vehicles with wheels in a diamond pattern.
The most serious and professional of the five rhomboids being exhibited was the Pininfarina X (sometimes also called the Pf-X), a wild but serious driveable design and engineering prototype built by the famous Turin-based styling house in 1960.
As with each of the rhomboids at Retromobile, the Pininfarina X had a cruciform platform with a single steering wheel at the front, and a single driving wheel at the rear, with two outrigger wheels on the sides positioned behind the four doors. Large fins at the rear, combined with an aerodynamic teardrop shape, were incorporated into Pininfarina’s ‘jet age’ design to help provide some lateral stability in crosswinds, like a dart. The prototype achieved an outstandingly low aerodynamic drag of just 0.23 – a figure that even the most modern fuel-efficient cars struggle to achieve today, and hugely impressive back in 1960.
A 1.1-litre Fiat engine was located at the rear of the car on one side, allowing space for luggage, and although it was a standard Fiat motor, the X achieved a 20 per cent higher top speed than the equivalent production-bodied Fiat 1100 from which it was borrowed, due to its slippery shape and low drag. As Pininfarina saw the experimental prototype’s teardrop shape as the most efficient way to minimise the resistance of a solid body passing through the air, the challenge was for its designers to adapt the shape of an automobile with four wheels and room for four passengers to the teardrop shape without becoming too large and impractical.
Unusually for a 1960s design concept, the X was engineered and built as a running driveable vehicle, with Pininfarina’s head, Batista ‘Pinin’ Farina, personally driving the X around to various car manufacturers to try and get the car into production, alas all to no avail. The main reason they all declined to build the X was that – aside from the bizarre layout, which would have surely put some new car buyers off – the X also possessed twitchy and unpredictable handling qualities- which would have definitely put everyone off.
The X was originally exhibited at the 1960 Turin Motor Show and the 1961 Brussels Automobile Show, after which it was returned to the Factory where it remained in the Pininfarina museum until 2007 when a well-known car collector acquired it.
Photography by Tom Shaxson