The Primus
Back in 1946, after being a seasoned pilot both in military and civilian flights, Eugenio Quiroga retired and opened a small car repair shop, following his passion for cars. A year later he wanted to buy a car for his son (which at the time was working as an engineer in ACM) but due to the lack of nice and cheap cars in the country, he decided to design one himself.
What started as a simple side project soon became time consuming and Eugenio saw lot of potentian on what he was building, so in 1948 officially founded Meliora Automotores (meliora is a latin word which means “better things”, “always better”, “ever better”, or, more fully, “for the pursuit of the better”) and presented his first prototype called Primum (“first” in latin).
The body work was inspired on european sports cars and made of aluminum, along with the steel spaceframe chassis everything was designed in home, except the drivetrain. Both the engine and the transmission came from ACM, but were modified to get more performance. The 3.5 liters inline 6 engine originally produced 103 hp, but Eugenio adjusted the pistons for more compression, modified the camshaft to a more agressive design and added a second carburetor, boosting the power up to 144 hp and the torque to 192 ft-lb. The transmission was the same 3 speed founded in the ACM-35, but with a differential with lower gear ratio. Since it only weighted around 900 kg, the car could easilly reach almost 180 km/h and hit 100km/h in 10 seconds. Since the car was still low budget, some compromises had to be made, like the lackof interior or the absence of sway bars.
2 more were produced, and used as a marketing to attract investors and future buyers to the new company.
Finally, in 1950 the Primum got road certified and hit the production line, just in time to participate in the Carrera Panamericana. Only 96 were produced from 1950-1952.
The production model has the same engine as the concept, but was less modified, producing only 138 hp and 187 ft-lb. Also includes a 4 speed transmission (from ADM) and safety bumpers (but no sway bars).
Top speed: 177.4 km/h
0-100 km/h: 8.6 s
1/4 mile: 16.74 s @ 139 km/h
Automation TT: 2:50
Airfield track: 1:42.65