According to the YouTube description from Vianor, the tractor is a 1956 Volvo BM Terrier with an added roll cage, adjustable front suspension and extended frame. The engine is thoroughly Swedish, and it's based on a Volvo 940 Turbo with a Volvo 240 head and Volvo 740 intercooler. However, it uses a Saab turbo Prospark ignition and fuel system. All told, the setup is claimed to make 225 horsepower and is capable of a top speed of 60 miles per hour.
That's not crazy power, but this tractor can certainly put it down. The farm machine has no problem smoking those big rear wheels and drifts easily.... although, it may be a tiny little bit unstable (hence the roll cage). If nothing else, this looks like the world's most fun way to be a farmer, that's for sure.