See other engines in this family
Mazda BP-Z3 specs: 1.839L (112.2 ci) 4-cylinder, 83 x 85 mm (3.2677 x 3.3465 in) bore and stroke, 10:1 compression. Rated 142 hp. Rod ratio and piston speed.
The Mazda BP-Z3 is close to square: 3.2677" bore against 3.3465" stroke, within 2.4%, which splits the difference between a high-revving layout and a torque layout. The 3.3465" stroke does not reach 4,000 ft/min of mean piston speed until about 7,150 RPM, so piston speed is not what limits this engine's revs — valvetrain and breathing are. Each of the 4 cylinders displaces 28.1 ci (460 cc).
10:1 on aluminum heads is in the range that usually runs on pump premium; aluminum sheds heat faster than iron, which makes the same number a little more forgiving.
It is one of 14 engines in the B-Series family, the largest at 112.2 ci. Factory fitments include the Mazda MX-5 Miata (NB), Mazda MX-5 Miata (NBFL).
| Displacement | 112.2 ci / 1.839 L |
|---|---|
| Bore | 3.2677" |
| Stroke | 3.3465" |
| Cylinders | 4 |
| Compression ratio | 10:1 |
| Bore/stroke ratio | 0.976 |
| Block material | cast iron |
|---|---|
| Head material | aluminum |
| Valvetrain | DOHC |
| Fuel type | gas |
| Advertised HP | 142 hp |
| Bore/stroke character | 0.976 — square — bore and stroke are within 5%, a balanced compromise |
|---|---|
| Mean piston speed at 6,000 RPM | 3,347 ft/min — conservative for a street engine |
| Displacement per cylinder | 28.1 ci |
| Static compression | 10:1 — in the range that usually runs on pump premium |
Each link opens the calculator with this engine's specs already filled in.