Historic Car Brands

The Italian companies, Grondona Comi & C and Miani Silvestri & C merged in 1899, forming Officine Meccaniche (OM), to manufacture railway equipment. Car production started in 1918, following OM’s takeover of the Zust car company of Brescia. 

Zust (Züst) had been founded by engineer Roberto Züst, an Italian industrialist of Swiss origin, who owned a precision tool manufacturing plant and who had experimented with prototypes of cars from around 1900.

In 1905, he founded the Zust company, to manufacture cars and commercial vehicles, powered by large-capacity four-cylinder engines, with displacements from 7.4 litres to 11.3 litres.

In 1906 Roberto Züst opened a second factory, in Brescia, to make smaller cars, but because of financial problems, that endeavour ceased in 1912 and production of larger Zust cars concentrated in Brescia, until 1914. 

In the meantime, in 1908, a Zust 28/45hp model participated in the 1908 New York to Paris Race – the longest automotive race ever conducted –  and finished third. (This race inspired the 1965 film, The Great Race.)

1912 Zust 28hp – Andy Dingley

The last new Zust models, the 2S 365 2.6-litre 15/25hp and the S305 4.7-litre 25/35hp, appeared in 1913.

The first OM car, the 1918 Tipo S305, was derived from an existing Zust model that was  powered by a 4.7-litre, in-line, four-cylinder, side-valve engine.

The birth of OM cars

In 1917, Zust was taken over by Officine Meccaniche of Milan, who continued to make the S305 until 1923, under the OM brand.

Additional OM models were the 1919 1.3-litre Tipo 465;  the 1920 1.4-litre Tipo 467 and 1921 1.5-litre Tipo 469. OM nomenclature combined the number of cylinders with the size of the cylinder bore, so the Tipo 465 was a four-cylinder car with a bore dimension of 65mm.

1929 OM Superba 665 – Stahlkocher

In 1923 came the Tipo 665 ‘Superba’ two-litre, six-cylinder model, with a side-valve engine, derived from the Tipo 465 four-cylinder model. This was by far the best known and most successful OM car model.

The Tipo 665 was successful in racing, winning top five positions in the two-litre class in 1925 and 1926 at Le Mans but its greatest achievement was the victory in the first Mille Miglia race in 1927, where Ferdinando Minoia and Giuseppe Morandi led an OM ‘1-2-3’ finish at an average speed of 77.7km/h (48.27mph) in an elapsed time of 21 hours, four minutes and 48 seconds. 

1927 Mille Miglia winning OM665, driven by Minoia and Morandi

Some racing OMs were equipped with Roots superchargers and later models were bored and stroked to 2.2 and 2.4 litres.

OM’s racing success with the Tipo 665 had led it to invest in a pair of racing specials, aimed at the AIACR World Manufacturers’ Championship, In 1926. 

OM debuted a Roots-supercharged 1.5-litre formula racing special, the Tipo 865. It was powered by a 117bhp at 6500rpm straight-eight, based on two Tipo 465 block dimensions, but with welded or brazed steel construction, much shorter piston stroke, roller-bearing crankshaft and a twin-overhead-camshaft cylinder head. 

Because the block was fabricated from steel plate the cylinder head bolts need to pass through it, to clamp the head to the crankcase. The camshafts were driven by a front timing case gear train and the valves were controlled by triple springs.

However, while the engine was then state-of-the-art, the chassis wasn’t in the top league, being merely a lowered and shortened road car chassis. Performance was also greatly hampered by the use of three-speed transmission. 

According to Italian High Performance Cars by Anthony Pritchard and Kenneth Davey (published by George Allen and Unwin 1967):

Start of the 1927 Italian Grand Prix – Bibliotheque nationale de France

‘One of the cars ran in the German GP at Avus, but retired for unspecified reasons…but they eventually ran in the 1927 Italian GP at Monza, where, after the retirement of much of the fast opposition, they finished second and fourth. 

“These cars can hardly, however be regarded as successful, as their performance was hampered by a three-speed gearbox, excessive weight (800kg dry) and inadequate roadholding.

‘One of these cars was brought to England by the OM concessionaire Rawlence, where it was modified by development engineer R F Oats. It ran quite well in Brooklands handicaps, but failed to finish in any of the long-distance events for which it was entered.’

(Motor Sport,  April 1964, reported that Oats poured lead into the U-shaped forward section of the frame, in an attempt to improve its road holding!)

Overhead valve specials

Rawlance imported around 350 OMs to England, where Oats developed an OHV version of the Tipo 665, of which six were built, to permit qualification in the 1929 TT. According to Motor Sport:

‘The English heads were cast iron and the combustion side was flat. Domed pistons (were fitted), because the position of the spark plugs did not leave room for trunk pistons. The cylinder block was very special, made in cast iron, with twelve 18mm spark plugs – six on each side, fixed in well-hidden holes.’

1931 OM Superba 665 SSMM with OHV conversion by Rawlance-Oats – Museo Nicolis

It seems that the complexity and cost of mounting its brief Grand Prix campaign put off OM’s directors and the company took a completely different direction, following expansion into producing OM trucks and buses in 1925. Licensed Swiss Saurer engines and other mechanical components were used in these commercial vehicles that HV has covered in the Truck Brands section.

1930 OM Touring – carrozzieri-italinai

However, OM car production concentrated on different body variants on the Tipo 665 chassis. According to MuseoAuto, the 1927 model list included various types of phaeton, including Mylord, Bateau, Weymann, Limousine coupé Deluxe, Landaulet coupé, Saloon and the expensive Cabrio Saloon convertible phaeton.

The automotive press praised road-holding that was exceptional for the time, smooth gear changing, efficient brakes, sharp acceleration and overall manoeuvrability.

MuseoAuto

At the Milan Show of 1931, OM showed a saloon on an N5 chassis and boasted that the car  ‘… embraces all the features of the great marque even though it fits a small capacity engine. 

‘A staid car with a sturdy, elegant, safe line…In this type of car, any dangerously refined mechanical excesses are rejected. 

‘The model stands firm as a clean-lined, absolutely safe mechanical construction.’

Decline and demise

However, OM was never a great volume car producer, with only around 7500 being manufactured since 1918 and, by 1930, the combined effects of the Great Depression, plus increasing competition saw its volumes drop to unsustainable levels.

In 1933, Fiat took over the OM company, principally for its commercial vehicle manufacturing value and OM car production ceased. A prototype car, the OMV Alcyone, that boasted hydraulic brakes and full synchromesh transmission was exhibited but never produced. 

OM Alcyone – carrozzieri-italinai

That may actually have been a blessing, because it featured a highly unconventional cylinder head, with exhaust-over-inlet, not the more popular inlet-over-exhaust (IOE)design. EOI engines worked on Moto Guzzi and Victoria air-cooled motorcycles, where the cylinder head could be positioned in the airstream, but cooling the head in a passenger car engine bay might not have been so easy. 

We’ll never know, because Fiat canceled the Alcyone project in 1934 and had its OM subsidiary concentrate on commercial vehicles.

Both Fiat and OM truck brands were absorbed into the IVECO conglomerate in 1975.

Achille Luciano Mauzan

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