Oldsmobile 371ci specs: 4.00 x 3.688 in (101.6 x 93.7 mm) bore and stroke, shared by all 4 versions. Displacement, compression and factory ratings.
| Displacement | 371 ci |
|---|---|
| Cylinders | 8 |
| Bore | 4.000" |
| Stroke | 3.688" |
| Compression | 8.8–10.0:1 |
| Advertised power | 240–312 hp |
| Years | 1957–1960 |
| Cylinder head data | 4 of 4 engines |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| Oldsmobile 371ci · 4" × 3.688" · 9.5:1 | 371 ci | 4" × 3.688" | 9.5:1 | 277 |
| Oldsmobile 371ci · 4" × 3.688" · 10:1 | 371 ci | 4" × 3.688" | 10:1 | 265–312 |
| Oldsmobile 371ci · 4" × 3.688" · 9.75:1 | 371 ci | 4" × 3.688" | 9.75:1 | 270 |
| Oldsmobile 371ci · 4" × 3.688" · 8.75:1 | 371 ci | 4" × 3.688" | 8.75:1 | 240 |
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.