1960 FSO Syrena Mikrobus Prototype

Of the prototype cars of the Polish Fabryka Samochodów Osobowych S.A., some were not an attempt to realize the dreams of designers and stylists but arose from the then-existing needs and were implemented by the existing technological and production conditions. One of these was the experienced 7-seater FSO Syrena Mikrobus, built in 1960 based on the FSO Syrena passenger car. The history of the creation of this small minibus and its design should be considered in several aspects.

First, none of the Polish car manufacturers offered after the war a small van or minibus of such a class that could be used in the small manufacturing sector, that is, in all types of small and medium-sized enterprises, as well as a car of such size that could typically be used in health care as an ambulance or a practical vehicle for mail. Therefore, there was a need to supply the market with a small delivery van, but one that would be cheaper to manufacture and purchase than the pick-up of the Warszawa 200P with a carrying capacity of 500 kg, presented at the FSO in 1958 (produced serially in 1959-1964) or a van based on it, made in small series or artisanal way. Due to the outdated production process and the rather expensive production technology of Warsaw, it was decided that it would be much cheaper to develop a car project, the starting point of which would be a minibus and a delivery van based on the design and use of the components of the FSO Syrena car, which at that time was already in mass production (at the same time, FSO had already made an experienced FSO Furgon van with a new body, but it did not go into series).

Secondly, no less important, the production of such a car could be carried out not at the FSO plant itself but one of the other car plants - this was due to the lack of technical capabilities of the FSO at that time. Thirdly, after 1956, the so-called ""political thaw,"" which led to a (temporary, unfortunately) economic recovery, caused many positive actions, including implementing many exciting initiatives of the creative community, including young Polish engineers. It was a time when the country created many interesting own developments, both those that subsequently served a long time (for example, the development and implementation of vans UK and Nysa) and those that, from the very beginning, was doomed to failure but showed potential (for example, the iconic Syrena Sport).

Considering the above factors, already at the end of 1957, the department of the chief designer of FSO, the head of which at that time was Charles Aimé Pionnier, Master of Science (had French roots - his mother was French), began to develop assumptions for a delivery car with a carrying capacity of about 500-600 kg or seven passengers, wholly based on the use of basic units and serial parts of the car Syrena 102. Given the assumption that the car would be produced in a small enterprise, it was decided to simplify the body's design as much as possible in terms of execution, excluding any parts that required stamping. Therefore, the body had to consist of a welded steel frame covered with leather from simple elements of sheet metal. The creators of the concept of this solution were specialists working in the department of the chief designer of FSO in the field of building car bodies, with the large and significant participation of the young designer Stanislav Lukashevich. Several design options for the Syrena versions were created on the sketches, including a van and a sanitary one, but eventually, a passenger version was chosen to build the prototype. A 1:5 gypsum model of such a car was made in the DGK FSO department, which, after the Sirens and the small car of 1956, occurred on the FSO only for the third time.

Using the unchanged design of the front part of the frame with the attachment points of the power unit and the front suspension from the production version of the Syrena 102, a new frame was made, longer in the rear and modified at the attachment point of the rear suspension. The modification was necessary due to the change compared to the production version of the Syrena rear suspension type car, based on a package of transverse torsion beams and trailing levers. This suspension was designed by engineer Antoni Drozdek and was also used in the parallel-built Syrena Sport prototype. The rejection of the high bracket of the rear transverse spring allowed the minibus to have a flat floor and any seat configuration, which indeed increased its functionality. As an aside, it is worth mentioning that the "torsion beam""" suspension was also part of the modernization plan of the usual passenger production Syrena, but it was never implemented. The next step in the creation of the prototype was to ""build the frame"" by installing a standard and unchanged in any part of the transmission and front suspension. Changes began in the future: the fuel tank was located horizontally in front of the transverse pipe, which housed a package of torsion beams made of the same flat bars as the top springs of Warsaw, and with a different location of the exhaust system. So that the spare wheel could be placed under the floor behind the rear axle, the exhaust pipe ended in front of the left rear wheel, and its output was directed outwards. To demonstrate the concept of the car and reduce the cost of building a prototype, it was decided that the ""skeleton"" / frame of the body will not be made of steel profiles but of wooden slats and will be attached to the frame with bolted joints. Thanks to his skills and experience in the construction of such structures, former master modeler Victor Rec was here an invaluable expert.

Stanislav, as mentioned above, Lukashevich developed the body structure. Thanks to engineer Jerzy Dembinski, who also worked on the Syrena Mikrobus project, fragments of handwritten sketches of individual nodes have survived. The finished frame of the body was then sheathed with simple or slightly formed sheets of skin, which were attached to the slats with screws. The exception was the use of plastic (glass-reinforced epoxy resin) for the hood - this decision was also made for reasons of economy; its shape was quite complicated and required the connection of several components; in addition, this technology was provided as cheaper when production was started. Parts from cars ""Warsaw"" and ""Siren"" were used for both external and internal body trim (headlights, direction indicators, switches, handles, mirrors, wipers). The new elements created from scratch for the minibus prototype were the seats (four single and one double) and the dashboard, designed by engineer Cesary Navrot. When the FSO Syrena Mikrobus prototype was completed in the summer of 1960, it was sent to the BKD (Road Construction Bureau) for road testing. In general, the car tested positive, except for one. It turned out that the tires used on it were 5.25 x 16 (the only suitable tires produced by the Polish industry) and could not withstand the expected load. Therefore, there could be no question of using the car as a 7-seater minibus unless we talk about five adults and two children.

However, launching it in series as an ambulance and postal service was still being considered. Unfortunately, the ""time of the thaw" in the PNR was slowly passing, and the transfer of the project to production "shut down." None of the plants wanted to produce a new minibus and its modifications. Due to its small size and freely configurable interior, the FSO Syrena Mikrobus can be considered one of the first (but not the first) in the world of "minivan" cars. (MPV), which appeared more massively only much later. Thus, FSO could be among the first to interest Europe with an exciting offer and, bringing this car to perfection, produce it in large quantities for a long time.

Some technical characteristics of FSO Syrena Mikrobus:

• Engine: power 19.9 kW (27 hp) at 3800 rpm, volume 746 cm3;

• Coupling: similar to the Syrena 101 - dry, single-disc with a disc equipped with spring dampers, with mechanical control;

• Transmission: as on the Syrena 101 - mechanical, with five gears (4 forward + backward), unsynchronized, in the general unit with the differential, the gear lever on the steering wheel;

• Drive: front;

• Steering mechanism: similar to Syrena 101 - worm type;

• Brake system: as on the Syrena 101 - hydraulic, single-circuit, drum type, mechanical auxiliary brake acting on the rear wheels;

• Chassis: frame-based design (upgraded frame of the production Syrena 101);

• Front suspension: independent - lower transverse arms; transverse leaf springs; telescopic hydraulic shock absorbers;

• Wheels and tires: 16-inch, tires 5.25-16;

• Length/width/height: 3800 mm/1550 mm/1640 mm - with load;

• Wheelbase: 2300 mm;

• The width of the front track: 1200 mm;

• Width of the rear track: 1240 mm;

• Transverse clearance: 185 mm;

• Prolonged clearance: 205 mm;

• Total weight of the car: 950 kg;

• Maximum permissible mass: 1,385 kg;

• Cargo version payload: 435 kg, loading area 2.2 m2, cargo compartment volume 2.8 m3, internal cargo compartment dimensions 1700x1300x1260 mm;

• Maximum speed: up to 95 km/h;

• Fuel consumption: 8.5-9.5 l / 100 km.

Source & Images: vk.com (Max Schavlev Aug 2022)