The Fiasa engine was produced in a number of stroke lengths but always of nearly the same bore. The first model was very oversquare, using a bore and a stroke of to produce a displacement of 1049 cc. The rod length was an ample , meaning that much larger strokes were possible without any negative consequences. It had a single-barrel
carburetor and the intake manifolds were narrow, restricting peak power while providing good performance at lower engine speeds. It had breakerless electronic ignition and chrome-treated exhaust valves with stellite seats, for increased durability. A larger version arrived in 1979, again tuned for low down torque. As exports to Europe commenced, the 1.3 was later bored out by 0.1 mm, to nudge the displacement above 1.3 liters. This allowed Italian motorists to drive a full on the
autostrada, rather than the to which cars under 1.3 litres were limited. The diesel derivative was also of this dimension. The Brazilian engines were also exported to Europe in large numbers, both for the
127,
Ritmo, and the later
Uno. The fully finished engines were shipped in large containers containing 144 engines each. The 1.05 was also installed in the
Autobianchi Y10, where it was also available with turbocharging. Fiat later made a very short-lived derivative, using a stroke. This was only installed in the sporty
Fiat Oggi CSS, which was built in 300 examples in 1984. This engine produces . The next version was an undersquare version with a much longer stroke, the version with a which was introduced for the
Fiat Fiorino in 1989. The little 1050 was discontinued in 1989 as well. The final iteration was developed to fit Brazil's new sub-1 liter tax category and was introduced in 1990. Displacing , it had an extremely short stroke of . With a single carburetor, the new engine's specifications were very similar to the 1.05. A higher-powered, twin-barrel ethanol-powered version was introduced in 1991 for the Uno Brio but was discontinued shortly thereafter as it could not meet the new emissions regulations which took effect in January 1992. With these, only the single-barrel 1.0 (now catalyzed) and the 1.5 remained available. The catalyzed 1.0 was not cost effective, and for 1993 Fiat switched to an electronically controlled, double-barrel Weber 495 carburetor and was able to forego the catalyst. The new "Mille Electronic" cost less to build and power was higher than before the new emissions impositions. However, the production cars appear not to have met the 1992 standards and in November 1995 Fiat was fined
R$ 3.93 million ($ in dollars) for the 429,928 non-conforming Mille Electronic/ELX sold between December 1992 to June 1995. Some (possible) engine capacities are equal to those of the Fiat
OHC engines,
OHV engines and
DOHC engines built in Italy, but these are not the same engines. ==Applications==