Surrey - It's a battle between two powerful diesel-powered German cars as Audi's SQ7 takes on the most powerful production diesel car in the world - the Porsche Panamera.
The 4.0-litre tri-turbo (with an electric compressor) in the Audi pushes it off the line in 4.9 seconds to reach 100km/h while the Porsche's claimed 0-100km/h time is 4.5 seconds.
Both cars channel power to all four wheels.
Top Gear said: "Today's Drag Race is a diesel shootout between an SUV and a saloon car, as Audi's SQ7 monster takes on the Porsche's supernaturally quick Panamera. Who do you think will finish first?"