| Fiat 124/OHV engine | |
| Manufacturer: | Fiat / Fiat Automóveis (Brazil) |
| Production: | 1966 - 1999 |
| Configuration: | Inline-4 |
| Valvetrain: | OHV 2 valves x cyl. SOHC 2 valve x cyl. |
| Fueltype: | Gasoline, Diesel |
| Fuelsystem: | Carburetor, Indirect injection |
| Coolingsystem: | Water-cooled |
| Displacement: | NaNcc |
| Bore: | 73mm 76mm 78mm 80mm 84mm |
| Stroke: | 71.5mm 90mm |
| Successor: | Fiat Twin-cam |
| Block: | Cast iron |
| Head: | Aluminium |
| Turbocharger: | In some versions |
Designed by Aurelio Lampredi, the Fiat 124 engine first appeared in the all-new Fiat 124 in April 1966. The in-line four-cylinder engine comprised an iron block with an aluminium cylinder-head with pushrod actuated valves. The belt-driven design was ahead of its time when introduced. European production of the petrol versions ended with the Fiat 131 in 1984, but later diesel derivatives continued to be built until 1999. It did have a longer life in its twin-cam iteration, which continued in production until 2000. While originally of an overhead valve design, an overhead cam version was added to the facelifted 131 in 1981. The capacity was initially 1197cc (in the Fiat 124), but eventually ranged between NaNcc. There were also three SOHC diesel iterations of 1.4, 1.7, and 1.9 litres. The last versions of this engine to be built were the diesels. The 1929cc direct-injected diesel version was the first direct-injection diesel to appear in a production passenger car, the Fiat Croma Turbo D i.d.
The Fiat 124 series engine was produced in a number of configurations differing in stroke and bore but maintaining a standard bore-spacing. The first model (124 A.000) was near square, using a bore and a stroke of NaNmm to produce a displacement of 1197cc. A larger 1438cc version arrived in October 1968, in the 124 Special. This has an 80mm bore.[1] The bore was increased to 76mm to give a displacement of 1297cc for the 131, which was also available in a 1.6-litre version with a 84mm bore. A variety of other bores and strokes were available. Several of the Brazilian Fiasa engines share their bore and stroke with the 124 series engines and were sometimes used in the same cars, but the engines are not related.
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 1400NaN0 on the autostrada, rather than the 1300NaN0 which was allowed for cars under 1.3 litres.
The 124-series engine has five main bearings, a cast iron block and a reverse-flow aluminum alloy head. Intake and exhaust are both located on the right-hand side of the engine.
There are also overhead camshaft versions of the 124-series engine. The first was the Fiat Twin Cam, which used the 124-series block with some modifications to use a DOHC valvetrain with a crossflow head. The Italian single overhead cam version arrived in 1981 and formed the basis for the three diesel versions.
The 1367cc diesel was available in turbocharged guise in the Uno Turbo D, while the larger 1.9-litre version was also available with direct injection.
There was also a two-litre pushrod version (6132 AZ 2000) for the 1974 to 1982 Fiat Nuova Campagnola; this has the 84mm bore of the 1.6 but combined with a 90mm stroke.[2]
| Bore (mm) | ||||||||
| 73 | 76 | 76.1 | 78 | 80 | 82.6 | 84 | ||
|---|---|---|---|---|---|---|---|---|
| 71.5 | 1197 OHV | 1297 OHV | 1301 OHV | 1367 SOHC, diesel | 1438 OHV | 1533 | 1585 OHV, SOHC | |
| 79.2 | 1326 | 1437 | 1441 | 1514 | 1592 | 1697 diesel | 1756 | |
| 90 | 1507 | 1633 | 1637 | 1720 | 1810 | 1929 diesel | 1995 OHV |
List of vehicles using variations of the Fiat 124-series engine (incomplete).