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Ford EAO 2000 specs: 122 ci (2.0L) 4-cylinder, 3.578 x 3.03 in (90.9 x 77 mm) bore and stroke. Rated 86-100 hp, 1971–1973. Used in the Ford Pinto. SOHC.
The Ford EAO 2000 is oversquare — the 3.578" bore exceeds the 3.03" stroke by 18.1% — a layout that favors airflow and RPM over leverage at the crank. The 3.03" stroke does not reach 4,000 ft/min of mean piston speed until about 7,900 RPM, so piston speed is not what limits this engine's revs — valvetrain and breathing are. A rod ratio of 1.65 is in the range most production engines fall in. Each of the 4 cylinders displaces 30.5 ci (500 cc).
It is one of 6 engines in the Ford 122ci family, all of them 122 ci — the differences between them are in compression, heads and rating, not displacement. 3 factory variants share these dimensions, rated from 86 to 100 hp across 1971–1973.
| Displacement | 122 ci / 2 L |
|---|---|
| Bore | 3.578" |
| Stroke | 3.03" |
| Cylinders | 4 |
| Configuration | I4 |
| Compression ratio | 8.2–9:1 (published figures vary) |
| Rod length | 5" |
| Rod ratio | 1.65 |
| Bore/stroke ratio | 1.181 |
| Block material | cast iron |
|---|---|
| Head material | cast iron |
| Valvetrain | SOHC |
| Fuel type | gas |
| Advertised HP | 86–100 hp |
| Years | 1971–1973 |
| Bore/stroke character | 1.181 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves |
|---|---|
| Mean piston speed at 6,000 RPM | 3,030 ft/min — conservative for a street engine |
| Rod ratio | 1.65 — moderate — the range most production V8s fall in |
| Displacement per cylinder | 30.5 ci |
Each link opens the calculator with this engine's specs already filled in.
These records share identical bore, stroke, displacement and compression. They differ by model year and factory power rating.
| Year | Advertised HP | Code |
|---|---|---|
| 1971 | 100 hp | EAO 2000 |
| 1972 | 86 hp | EAO 2000 |
| 1973 | — | EAO 2000 |
1 factory vehicle, 1971–1974. Each year opens that model's engine table.