Plymouth 303ci specs: 3.813 x 3.313 in (96.8 x 84.1 mm) bore and stroke. Displacement, compression and factory ratings, plus rod ratio.
| Displacement | 303 ci |
|---|---|
| Cylinders | 8 |
| Bore | 3.813" |
| Stroke | 3.313" |
| Compression | 9.3:1 |
| Advertised power | 240 hp |
| Years | 1956 |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| Plymouth 303ci (1956) | 303 ci | 3.8125" × 3.3125" | 9.25:1 | 240 |
This family is represented by a single engine in the database: 303 ci, 8 cylinders, a 3.8125" × 3.3125" bore and stroke.
All are oversquare — bore larger than stroke, which favours revs over low-end torque.
Each engine page carries rod ratio, mean piston speed, bore/stroke character and cylinder head specs where published, and links into the calculators with its dimensions already filled in.