Mazda 13B specs: 80 x 80 mm (3.1496 x 3.1496 in) bore and stroke, shared by all 5 versions. Displacement, compression and factory ratings, plus rod ratio.
| Displacement | 80 ci |
|---|---|
| Cylinders | 2 |
| Bore | 3.150" |
| Stroke | 3.150" |
| Compression | 8.5–10.0:1 |
| Advertised power | 110–280 hp |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| 13B (Carbureted) | 80 ci | 3.1496" × 3.1496" | 9.2:1 | 110 |
| 13B · 3.150" × 3.150" · 9.4:1 | 80 ci | 3.1496" × 3.1496" | 9.4:1 | 130–146 |
| 13B-T (FC) | 80 ci | 3.1496" × 3.1496" | 8.5:1 | 182 |
| 13B · 3.150" × 3.150" · 9:1 | 80 ci | 3.1496" × 3.1496" | 9:1 | 200–280 |
| 13B-MSP (Renesis Low Power) | 80 ci | 3.1496" × 3.1496" | 10:1 | 189 |
Compression spans 8.5:1 to 10:1, so fuel requirements differ meaningfully between members — worth checking before assuming parts interchange.
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.