Forgotten prototype that's seldom seen could reach supercar speeds with just a one liter engine
- The OSI Silver Fox was a Le Mans prototype from the 1960s
- It had a small Renault-Alpine engine under the hood
- No one knows how fast it would have been around Le Mans
Published on Jun 01, 2025 at 9:37 PM (UTC+4)
by Henry Kelsall
Last updated on May 29, 2025 at 7:29 PM (UTC+4)
Edited by
Tom Fenton
A forgotten Le Mans prototype could once hit incredible top speeds with a small 1.0-liter engine.
This is the Silver Fox prototype racer, a small race car that recently emerged at the Villa d’Este several decades after its public unveiling.
It is one of the most bizarre race cars ever made, with it first emerging in the late 1960s as its manufacturer looked to take on the famous Le Mans 24 Hours.
But it never got to race at the iconic event, and thus it became one of motorsport’s greatest ‘what ifs’.
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The OSI Silver Fox was built by Officine Stampaggi Industriali (OSI).
This was a small Italian outfit that was usually found producing low-volume sports cars for companies such as Alfa Romeo.
In the mid-1960s, the company decided that it wanted to put its name out into the wider world and take part in racing.
The Silver Fox is the product of that development.
The unusual car has a twin-hull layout, looking almost like a catamaran.
Its two narrow pods created a floating-wing-like appearance, with the engine mounted on the left side.
Sat behind the cockpit is a 1.0-liter Renault-Alpine four-cylinder engine.
To balance the weight out, the driver sat in the right-hand side pod.
Despite its small engine size, the Silver Fox had an impressive top speed of 155mph.
Not bad for a car with an engine you’d normally find in a daily driver family car like a Toyota Corolla.
It also had novel aerodynamics, with three large spoilers connecting its pods.
These were also adjustable, depending on the track that the car was racing on.
As images of the car show, it was an unconventional design.

OSI folded in 1968, and the one-off prototype never made it to Le Mans.
Thankfully, and against all the odds, this remarkable prototype has survived.
Its appearance at the Villa d’Este was one of its first public appearances in a long time.
Nestled among all the other racing cars, the Silver Fox still stands out and easily draws a crowd.
We will never know how well the car could have done at Le Mans, but we so wish we could find out.
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Henry is a content writer with nearly ten years experience, having written for various publications since 2017. Qualifying with a Sports Journalism degree from Staffordshire University, Henry loves all things automotive but has a particular soft spot for classic Japanese cars and anything Lancia. He also has a curious passion for steam locomotives.