year of the race at the Pradědský circuit near Karlova Studánky on June 19, 1927 (class up to 1100 cm3)[2] started by a graduate of the Brno Technical University, Eng.

The Z 6V reached a top speed of around 175 km/h and had very good acceleration, but also had many problems such as a tendency to burn through the bottom of the pistons controlling the exhaust port.

He was already very embittered by the tragic accident of his friend Čeňko Junko in the summer of the same year at the German Nürburgring.

The engine block was equipped with two crankshafts connected by a toothed gear, allowing the intake and exhaust to be controlled by the edges of the pistons with a small offset.

The fuel mixture, ignited by a dozen Champion spark plugs connected to two Scintilla aviation magnetos located transversely by the flywheel, was prepared by two Zenith TD 30 triple-diffuser carburetors.

[1] With an output of 55 kW (75 hp) at 5500 rpm and a three-speed gearbox with reverse gear (3+Z), the car reached a maximum speed of 175–180 km/h.

[2] According to not entirely confirmed reports, the engine of this Z 6V car was supposed to have been used for the first time already at the 2nd year of the Praděd Circuit (June 19, 1927).

Rychard Müttermüller won the laurel in the category up to 1.1 l, which was run for 10 laps (224 km) for Zbrojovka from Brno[10] in a time of 3:06:15.7 h. Zetka's success was also completed by the third place of Maj. retired, Karel Stohanzl[11] (racing from that date under the pseudonym "Flieger", which he chose as a former military pilot in the Austro-Hungarian army) and the sixth place of Bedřich Soffer, who drove the fastest lap of the class in 18:10.9 min.

It was a 1085cc two-stroke turbocharged six-cylinder with a displacement of 1085 cc, designated M2, and this engine was later fitted to the Z 6V sports-racing special.

[13] Soffer finished in 6th place, although in the 3rd lap he rammed into Káš's Imperia, which skidded and remained standing across the road.

Although these cars had not yet completely left the trial stage and were sent to the race, one might even say experimentally, they managed to win for the first time in the hands of excellent drivers.

[15] "Flieger" with Müttermüller took the first two places in the class of sports cars up to 1.1 l on the Z 4V (M6 engine - two-piston two-stroke two-cylinder, longitudinally doubled, displacement 0.995 l, max.

The success of Zbrojovka was completed by the first 3 places in touring cars from 18 to 1000 cc, where the drivers behind Zetky occupied the podium in the order of Karel Divíšek, Jar.

Liebig in an Amilcar won in 3:38:35.8 min ahead of Arnošt Procházka, Josef Mamula, Vodička and Karel Divíšek in Zetky (2nd-5th place).

[22] For the 5th year of the national race to the Knovíz-Olšany hill (June 24, 1928), 39 machines came to the start, including 21 motorcycles, 6 sidecars and 12 cars.

[24] After a one-year break due to track repairs, on April 28, 1929, the 12th edition of the international race to the Zbraslav-Jíloviště hill attracted 100,000 spectators.

[26] Brněnská Zbrojovka commissioned engineer Vladimír Souček,[27] who joined Zbrojovka on January 1, 1929 (after the departure of engineer Mackrle), to rework the Z 6V and prepare it for the sports car race at the Grand Prix of the Sports Car Nations, which took place at the German Nürburgring on July 14, 1929.

The Z 6V was lowered, the engine was moved a bit back (the compressor no longer "peeped out" in front of the radiator), the suspension of the axles and the brake system were redesigned.

It was fitted with dual Bosch magneto ignition, new Roots superchargers and the stressed pistons were cast with a copper cooling liner.

The factory driver Karl Stohanzl led his category for almost the entire race, but in the penultimate lap he blew his pistons again.

[28][b] After the failure at the Grand Prix of Nations at the Nürburgring and also after the tragic accident of Bedřich Soffer, Zbrojovka stopped the entire Z 6V/Z 2 and Z 4V project.