Hyundai Nu specs: 81 x 97 mm (3.1890 x 3.8189 in) bore and stroke, shared by all 2 versions. Displacement, compression and factory ratings, plus rod ratio.
| Displacement | 121.9–122 ci |
|---|---|
| Cylinders | 4 |
| Bore | 3.189" |
| Stroke | 3.819" |
| Compression | 10.3:1 |
| Advertised power | 147–164 hp |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| G4NA | 122 ci | 3.189" × 3.8189" | 10.3:1 | 147 |
| 20 | 121.9 ci | 3.189" × 3.8189" | 10.3:1 | 164 |
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.