Which Fiat 125 Version Should You Choose?
The Fiat 125 catalogue contains one generation, one Sedan body style and four listed versions produced from 1967 to 1982. Because there is no generation change to compare, the buying decision comes down to engine output and transmission: the 90 hp 1.6 MT, 90 hp 1.6 AT, 100 hp 1.6 MT and 100 hp 1.6 AT.
The Fiat 125 catalogue contains one generation, one Sedan body style and four listed versions produced from 1967 to 1982. Because there is no generation change to compare, the buying decision comes down to engine output and transmission: the 90 hp 1.6 MT, 90 hp 1.6 AT, 100 hp 1.6 MT and 100 hp 1.6 AT. All four use a 1,608 cc Gasoline engine with 4 Inline cylinders, 2 valves per cylinder, a Carburetor and RWD. The 100 hp 1.6 MT offers the strongest measured performance and the best weight-to-power ratio, while the 90 hp 1.6 MT is the lightest version. Buyers who specifically want an Automatic can choose between the lighter 90 hp car and the more powerful 100 hp car, although top speed is not measured for the latter.
Fiat 125 generations and version choice
The Fiat 125 has one generation in the supplied catalogue. The 1 generation ran from 1967 to 1982 as a Sedan and contains four versions. There is therefore no newer or older generation with different specifications to weigh against another: every comparison is within the same generation. The shared specification includes a 1,608 cc Gasoline engine, 4 Inline cylinders, Carburetor fuel delivery, RWD, independent spring front suspension, independent leaf-spring rear suspension, and disc brakes at both ends.
The four entries form two output groups. The lower-output 1.6 MT and 1.6 AT produce 90 hp (66 kW) at 5,600 rpm and 127 Nm at 3,500 rpm. The higher-output 1.6 MT and 1.6 AT produce 100 hp (74 kW) at 6,000 rpm and 130 Nm at 4,000 rpm. Moving to the higher-output specification adds 10 hp, 8 kW and 3 Nm, while the displacement remains unchanged.
Fiat 125 engine and specs comparison
| Exact version | Output | Torque | Displacement | Fuel | Cylinders | Layout | Boost | Gearbox | Drive |
|---|---|---|---|---|---|---|---|---|---|
| 1.6 MT (90 hp) | 90 hp / 66 kW at 5,600 rpm | 127 Nm at 3,500 rpm | 1,608 cc | Gasoline | 4 | Inline | not measured | 4-speed Manual | RWD |
| 1.6 AT (90 hp) | 90 hp / 66 kW at 5,600 rpm | 127 Nm at 3,500 rpm | 1,608 cc | Gasoline | 4 | Inline | not measured | 3-speed Automatic | RWD |
| 1.6 MT (100 hp) | 100 hp / 74 kW at 6,000 rpm | 130 Nm at 4,000 rpm | 1,608 cc | Gasoline | 4 | Inline | not measured | 5-speed Manual | RWD |
| 1.6 AT (100 hp) | 100 hp / 74 kW at 6,000 rpm | 130 Nm at 4,000 rpm | 1,608 cc | Gasoline | 4 | Inline | not measured | 3-speed Automatic | RWD |
Engine capacity does not distinguish these cars, but specific output does. The 90 hp versions produce approximately 56.0 hp per litre, whereas the 100 hp versions produce approximately 62.2 hp per litre. That is about 6.2 additional hp per litre from the higher-output specification.
Both engines have an 8.8 compression ratio and an 80 × 80 bore and stroke. Each has 2 valves per cylinder. Boost is not measured, engine location is not measured, and the fuel grade is not measured.
Transmission choice creates another clear difference. The 90 hp 1.6 MT has a 4-speed Manual, and the 100 hp 1.6 MT has a 5-speed Manual. Both 1.6 AT entries use a 3-speed Automatic. Consequently, the 100 hp 1.6 MT combines the highest output with the largest number of forward gears in the data.
Fiat 125 performance and mpg
| Exact version | 0–100 km/h | Top speed | City consumption | Highway consumption | Combined consumption |
|---|---|---|---|---|---|
| 1.6 MT (90 hp) | not measured | 160 km/h | not measured | not measured | not measured |
| 1.6 AT (90 hp) | not measured | 155 km/h | not measured | not measured | not measured |
| 1.6 MT (100 hp) | not measured | 170 km/h | not measured | not measured | not measured |
| 1.6 AT (100 hp) | not measured | not measured | not measured | not measured | not measured |
The 100 hp 1.6 MT has the highest measured top speed at 170 km/h. It is 10 km/h faster than the 90 hp 1.6 MT and 15 km/h faster than the 90 hp 1.6 AT. Among the two 90 hp cars, choosing the 4-speed Manual rather than the 3-speed Automatic corresponds to a 5 km/h higher measured top speed.
The 100 hp 1.6 AT cannot be ranked by maximum speed because its top speed is not measured. Acceleration from 0–100 km/h is not measured for any version. City, highway and combined fuel consumption are also not measured for all four versions, so the data does not support an mpg or economy-based recommendation. CO₂ output and emissions class are not measured for any version.
Fiat 125 dimensions, weight and tank capacity
Overall exterior dimensions are not measured for the listed versions, so the four cars cannot be compared by length, width or height. Ground clearance and wheel sizes are also not measured across the range. Weight and fuel-tank capacity are available:
| Exact version | Kerb weight | Gross weight | Tank | Ground clearance | Wheel sizes |
|---|---|---|---|---|---|
| 1.6 MT (90 hp) | 1,030 kg | 1,430 kg | 45 L | not measured | not measured |
| 1.6 AT (90 hp) | 1,050 kg | 1,450 kg | 45 L | not measured | not measured |
| 1.6 MT (100 hp) | 1,055 kg | 1,455 kg | 45 L | not measured | not measured |
| 1.6 AT (100 hp) | 1,060 kg | 1,460 kg | 45 L | not measured | not measured |
Every version has a 400 kg difference between kerb and gross weight. The 90 hp 1.6 MT is the lightest at 1,030 kg, while the 100 hp 1.6 AT is the heaviest at 1,060 kg, a difference of 30 kg. At 1,050 kg, the 90 hp 1.6 AT is 20 kg heavier than its Manual counterpart. The higher-output 1.6 AT weighs 5 kg more than the higher-output 1.6 MT.
Weight per horsepower makes the output differences easier to compare. The 90 hp 1.6 MT carries about 11.44 kg per hp, and the 90 hp 1.6 AT carries about 11.67 kg per hp. The 100 hp 1.6 MT improves that figure to 10.55 kg per hp, while the 100 hp 1.6 AT reaches 10.60 kg per hp. On this measure, the 100 hp 1.6 MT has the strongest power-to-weight proposition.
Fiat 125 reliability and problems data
Reliability ratings, failure records, repair frequency and model-specific problems are not measured in the supplied data. The common Carburetor system, RWD layout, suspension arrangement and disc-brake specification identify what the four versions share, but they do not establish reliability. A purchase decision based on problems or maintenance risk therefore cannot be made from these figures alone.
Which Fiat 125 version should you buy?
Choose the 100 hp 1.6 MT if measured performance is the priority. Its 100 hp and 130 Nm are the highest figures available, its 170 km/h top speed leads the measured versions, and its 10.55 kg-per-hp ratio is the best in the range. It also has a 5-speed Manual, compared with the 4-speed Manual in the 90 hp 1.6 MT and the 3-speed Automatic in both 1.6 AT versions.
Choose the 90 hp 1.6 MT if low kerb weight matters more than maximum output. At 1,030 kg, it is 25 kg lighter than the 100 hp 1.6 MT and 30 kg lighter than the 100 hp 1.6 AT. Its measured top speed is 160 km/h, which is 10 km/h below the more powerful Manual but 5 km/h above the 90 hp Automatic.
For an Automatic, the 100 hp 1.6 AT provides 10 hp and 3 Nm more than the 90 hp 1.6 AT while adding 10 kg of kerb weight. Its weight-to-power figure is about 10.60 kg per hp, compared with about 11.67 kg per hp for the 90 hp Automatic. However, its top speed is not measured, so that calculated advantage cannot be confirmed with a maximum-speed comparison. The 90 hp 1.6 AT is the Automatic choice with a recorded top speed—155 km/h—and the lower kerb weight of the two Automatic entries.
On the available numbers, the 100 hp 1.6 MT is the clearest all-round choice. The 90 hp 1.6 MT makes the strongest case for minimum weight, and the 100 hp 1.6 AT is the numerical choice for buyers who require an Automatic. Fuel economy, acceleration, reliability, problems and price are not measured, so none should be used to claim that one Fiat 125 version is cheaper to run, quicker from rest, more dependable or better value.