A 1993 Volvo Is Being Turned Into an Openpilot Test Bed for a Winter Rally

# A 1993 Volvo Is Being Turned Into an Openpilot Test Bed for a Winter Rally

*Event date: 2025-01-04*

A developer-engineer project is turning a 1993 Volvo 940 Estate into something the car was never designed to be: a vehicle that can host openpilot-style driver assistance hardware on a long winter rally. The project is aimed at the Carbage Run 2025 Winter edition, a six-day drive through Sweden to the polar circle and back to Helsinki, with a field of roughly 400 cars and a route of about 6,000 kilometers.

The appeal of the event is part endurance test, part originality contest. The rules require a car that is at least 20 years old and worth less than €1,000, which makes the 940 Estate a fittingly odd platform for an advanced retrofit. The builder behind the project, who says he has worked at comma.ai for about five years as a hardware engineer, frames the challenge as a chance to make an old car behave like a much newer one without pretending that the underlying hardware has suddenly become modern.

That difference matters. openpilot is built to work with recent cars that already have the electronic machinery needed for steering, throttle and braking control. The Volvo does not. Its steering is hydraulic, the accelerator uses a cable, and the brake booster is vacuum-based. In other words, nearly every control surface that modern assistance systems expect to talk to still has to be invented from scratch in physical form.

The most striking part of the conversion is the steering solution. Instead of trying to redesign the Volvo’s original steering rack, the project uses an electric power steering unit and ECU from a 2020 Toyota Corolla. The Corolla motor normally sits behind the dashboard on the steering column and amplifies driver torque. In the Volvo, the team cut away the original straight steering column, welded the Toyota and Volvo interfaces together, and mounted the EPS assembly in the space behind the dash.

That approach is mechanical as much as it is electronic. The Toyota column had to be shortened and adapted, and the team added bracing from the original steering frame so the assembly could be mounted securely once it had been rebuilt around the Volvo’s layout. The Corolla setup also includes an external steering angle sensor, which the builders had to adapt to the Volvo column with a machined bushing so the system could read an absolute steering position rather than just relative movement.

The article says there was enough room under the dashboard to fit the extra hardware without major surgery to the cabin, which is a useful break for a retrofit that already asks a 30-year-old car to host modern actuator gear. On the electrical side, the basic hookup is described as surprisingly straightforward: ground, constant 12V, an ignition signal and CAN to the angle sensor. With that in place, the EPS comes alive and behaves as though it were still in a Toyota, even if it is missing the rest of the original vehicle context it expects.

The piece also makes clear that the retrofit is not yet elegant. Running both the hydraulic assist and the electric assist together makes the wheel feel light, but the system does not naturally self-center in the way the builder wants. That is the sort of detail that explains why retrofitting old cars is more than a gadget exercise: it is an engineering negotiation with physics, packaging and control logic all at once. The project may be playful in spirit, but its first chapter is a serious reminder that modern driving assistance is really a stack of actuators hiding beneath the dashboard.