In 1933, the PKP bought a fast petrol railcar from Austro-Daimler in Austria that formed the basis of the BBÖ VT 63. This one had two 80 hp engines, each powering one axle of a two-axle bogie via a Voith hydraulic transmission. The bogies were special in that the wheels had air-filled rubber tires. The railcar reached a top speed of 100 km/h, but was underpowered for the needs of the PKP. So Klemens Stefan Sielecki improved the vehicle by replacing the petrol engines with 125 hp diesel engines supplied by MAN, what increased the top speed to 115 km/h.
Five of this type were built by Fablok with chassis still being delivered from Austro-Daimler. They were officially designated “Pociąg Motorowo-Ekspresowy” (MtE), but quickly got the nickname “Luxtorpeda”. Their main tasks were connections between Kraków and spa towns in the Carpathians. After they were used by the Germans in World War II, only two were surviving after the end of the war. The last of these was retired in 1954.