Audi EA189 specs: 81 x 95.5 mm (3.1890 x 3.7598 in) bore and stroke, shared by all 2 versions. Displacement, compression and factory ratings, plus rod ratio.
| Displacement | 121–121.9 ci |
|---|---|
| Cylinders | 4 |
| Bore | 3.189" |
| Stroke | 3.760" |
| Compression | 16.5:1 |
| Advertised power | 143 hp |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| 20 TDI I4 CR | 121.9 ci | 3.189" × 3.7598" | 16.5:1 | 143 |
| 20 TDI CR | 121 ci | 3.189" × 3.7598" | 16.5:1 | 143 |
All are undersquare — stroke larger than bore, favouring torque low in the range.
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.