Volkswagen's record-breaking ID.R time attack racer has a 680 horsepower electric powertrain comprised of two electric motors, located at each axle, and a large 43 kWh lithium-ion battery pack.

The ID.R is the first-ever EV race car made by Volkswagen, so the automaker needed a vehicle to test the prototype electric powertrain in before installing it in the back of the ID.R.

You can't just drop a groundbreaking electric powertrain with nearly 700 horsepower in any old car, though. After all, the radical ID.R has a ton of downforce and extra sticky slick tires, so a road car wouldn't be representative of the powertrain's torque delivery and overall driving characteristics.

VW turned to the only other tarmac race car in its stable, then: the Golf GTI TCR.

VW actually showed this unique Golf GTI TCR prototype in a video released last year documenting the ID R's development process, but we didn't notice it until now.

The international TCR rulebook has relatively modest regulations that allow for production-based 2.0-liter turbocharged cars with 300 to 350 horsepower. The ID R's electric motors are therefore much more powerful than the four-cylinder turbo that is usually found underneath the hood of the Golf GTI TCR, but the little touring car seemed to handle the extra power just fine.

A touring car series for electric TCR cars, dubbed the E TCR Series, is expected to launch in 2020. VW Group brand SEAT is the only manufacturer to have unveiled a concept racer for the E TCR Series and not surprisingly, it featured the same 680 hp twin-motor setup as the ID.R. So in addition to serving as a testbed for the ID.R's powertrain, the electric Golf GTI TCR seen here may also preview a new E TCR car from VW - although we haven't heard anything official yet.

Check out the video of the ID.R's development below.

[Source: FCP Euro Blog ]