Watch A Mazda Racecar Run At 120 MPH Down A Victorian Tunnel Designed For Steam Trains

The Catesby Tunnel is open again for the first time since it was closed to trains in 1966. Now, though, it’s running some of the most sophisticated race cars in the world, rather than steam trains.

Multimatic said today that it has successfully conducted its first full-size test in the tunnel, with driver Andy Priaulx running at a constant speed of 120 mph (193 km/h). The run was a validation test, though, so the race team sent a car it has a lot of experience with to learn about the tunnel, rather than the car itself.

The team’s Mazda DPi race car has been on racetracks and in full-size wind tunnels, and a model of it has been in scale model wind tunnels many times. That’s to say nothing of the hours and hours of computer testing that it has been subjected to. Multimatic, therefore, has a pretty good sense of its aerodynamics properties.

Read Also: What Do You Do With An Empty Victorian Railroad Tunnel? Turn It Into A Wind Tunnel, Of Course

The test, though, showed that the tunnel returned results that correlated with the wealth of information that the team has already collected on the car, which is good news. That proves that the 1.6-mile-long (2.7 km) tunnel is an effective alternative (or complement) to the conventional wind tunnel.

“Compared to conventional wind tunnels, this is better because it’s real,” said Larry Holt, Multimatic‘s head of motorsport. “In a moving ground plane wind tunnel, the car is stationary and the wind is blown over it by a massive fan and flow conditioning set-up, and a belt is arranged to move under the car at a coordinated speed. It’s a very sophisticated configuration but the car is still stationary and that constitutes the not totally real piece.”

At Catesby, cars are allowed to drive through the arrow-straight tunnel at speed. That means that, despite being a controlled environment, it’s more like what a car will be subjected to in real life.

“Catesby provides the real world without the weather,” said Holt. “You have a moving car, a real road surface, a controlled environment, and we can run 24 hours a day, whatever the season. It is a perfect 2.7 kms of controlled atmosphere. That’s the kind of consistency you need when you are chasing incremental gains.”

If driving down a relatively narrow tunnel at 120 mph sounds a little scary to you, you’re not alone. But according to Priaulx, it was all very comfortable, and he believes that higher speeds are easily achievable.

“At the start it felt a little odd to jump into a race car and drive flat out through a 2.7 km tunnel, but the team assured me that the end was very clearly marked!” he said. “Catesby Tunnel is an incredible facility, and it doesn’t surprise me at all to know that Multimatic chose to be an early adopter and primary client of the facility.”