One-off Subaru X-100 concept car was shaped like a plane and designed with the goal of crossing the US on a single tank of gas

The Subaru X-100 is pretty unusual, even by the standards of concept cars.

For one thing, it’s shaped like a plane.

And for another, it was designed with a very ambitious goal in mind – crossing the US on a single tank of gas.

The work of designer Alex Tremulis, this one-off car ended up being pitched to the CEO of Subaru.

The Subaru X-100 is quite literally one of a kind

This project was born in a time of crisis, namely the 1973 oil embargo.

Lasting from October 1973 to March 1974, this crisis saw a barrel of oil shoot up in price from approximately $3 to $12. Which, given the current prices, sounds like a great problem to have.

Unfortunately, back then, it hit Western economies with high inflation, and some gas stations famously ran out of fuel.

Queues of cars became a common sight, with many states implementing rationing.

Amid this chaos, a conversation around energy policy emerged.

And that’s how the Subaru X-100 was born.

Auto designer Alex Tremulis, who worked on the Tucker 48 and Ford Thunderbird, designed it and pitched it to Harvey Lamm, the CEO of Subaru America.

It was angled as a way to gain publicity through its extreme efficiency.

For the body, he used a vintage airplane wing tank as the basis, making it look like a Colonial Viper from Battlestar Galactica.

However, this thing was remarkably light – weighing only 70lbs in total.

A 500cc engine powered it, lifted from the Subaru Rex.

In theory, it all sounds very good – but how did it work in practice?

What happened when this concept car was taken out onto the track?

In August 1980, the X-100 got its big debut at the Ontario Motor Speedway.

By this point, the US was in the grips of a second oil crisis, so the timing for a test drive couldn’t have been better.

On its first attempt, it fell short of the 100-mile mark on one gallon of gas.

Second time around, it successfully traveled more than 100 miles on a single gallon at a relatively steady speed of 55mph.

Unfortunately, we never got to see how it fared on a cross-country trip as a planned drive from California to Florida never materialized.

As a result, the X-100 spent decades in storage before going up for display at the Lane Motor Museum in Nashville.

Alas, it’s a sign of what could have been, as concept cars often are.

This surreal Audi was designed in the 1930s but didn’t reach physical form until 2024.

Then there was this Ford concept car made back in 1983, which was something of a trendsetter.

And who could forget the downright inexplicable? The Ford Nucleon – need we say more?