Audi apprentices at the Neckarsulm factory in Germany have given a 1971 NSU Prinz 4 an all-electric drivetrain. The restored car, called the Audi EP4, aims to combine speed, aesthetics, and electric technology. The project was undertaken in honor of the factory’s 150th anniversary.

EV Conversion NSU Prinz 4 EV Conversion NSU Prinz 4

The EP4 features an electric motor from a 2020 Audi e-tron, providing it with 240 horsepower. This makes the restored car eight times more powerful than the original Prinz 4. 

The apprentices made major adjustments to the Prinz 4’s exterior. The apprentices replaced the Prinz 4 base with an Audi A1 base, leading to a significantly wider vehicle. They also added a splitter to the bottom bumper to increase traction. 

In addition, drivers can fix the restored car’s trunk into a half-open position. This allows cool air to enter while showcasing the new electric power system. 

EV Conversion NSU Prinz 4

The apprentices stripped down the Prinz 4’s interior to the essentials. The restored EP4 features bucket seats and black-painted surfaces. A single-board computer shows all instruments and displays. 

The project allowed the apprentices to gain knowledge about the EV manufacturing process while showcasing their talent.

NSU produced the Prinz 4 between 1962 and 1973. Auto experts considered the Prinz 4 a mediocre vehicle that offered no distinct advantages. The Prinz 4 also lacked a heater, in contrast to most other cars of its time. Nevertheless, the Prinz 4 has maintained a dedicated following among some antique car lovers. 

NSU was purchased by Volkswagen in 1969 and became part of its Auto Union brand. Volkswagen’s Auto Union brand eventually evolved into Audi. 


EV Conversions of Classic Cars as a Business

Although the Prinz 4’s EV conversion was merely an educational project, more and more businesses are profiting from EV conversions of classic cars. One such business is the UK company Electrogenic. 

In November 2022, Electrogenic announced that it would be expanding into the US. Electrogenic has assembled an EV conversion kit consisting of the company’s own manufactured technology, which includes circuit boards, dashboards, and hill descent control functions. Electrogenic has sold these EV conversion kits to businesses in Vermont and Texas as part of its new global installer network. 

The classic car conversion business is still in its early stages. Only 1% of antique car owners in the US, UK, and Canada had converted their vehicles into EVs, according to a May 2022 study. In light of this opportunity, Audi would be wise to launch a pilot project in which it sells restored classic cars. 

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