BMW 328ci specs: 85 x 79 mm (3.3465 x 3.1102 in) bore and stroke. Displacement, compression and factory ratings for each, plus rod ratio and piston speed.
| Displacement | 328 ci |
|---|---|
| Cylinders | 12 |
| Bore | 3.346" |
| Stroke | 3.110" |
| Advertised power | 322 hp |
| Years | 1995–2001 |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| M73B54 | 328 ci | 3.3465" × 3.1102" | — | 322 |
This family is represented by a single engine in the database: 328 ci, 12 cylinders, a 3.3465" × 3.1102" 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.