See other engines in this family
Ford Mazda BP specs: 112.3 ci (1.8L) 4-cylinder, 3.268 x 3.346 in (83 x 85 mm) bore and stroke. Rod ratio and piston speed worked out.
The Ford Mazda BP 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).
It is one of 5 engines in the Mazda-built Fours family, the smallest at 112.3 ci.
| Displacement | 112.3 ci / 1.8 L |
|---|---|
| Bore | 3.2677" |
| Stroke | 3.3465" |
| Cylinders | 4 |
| Bore/stroke ratio | 0.976 |
| Fuel type | gas |
|---|
| 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 |
Each link opens the calculator with this engine's specs already filled in.