Bore, stroke, displacement and compression for all 11 Subaru FA engines, compared side by side. Plus rod ratio and head specs where published.
| Displacement | 121.9–146.5 ci |
|---|---|
| Cylinders | 4 |
| Bore | 3.386–3.701" |
| Stroke | 3.386" |
| Compression | 10.6–12.5:1 |
| Advertised power | 200–300 hp |
| Years | 2015–2026 |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| FA24F | 146.5 ci | 3.7008" × 3.3858" | 10.6:1 | 271 |
| Fa24 NA | 146 ci | 3.7008" × 3.3858" | 12.5:1 | 228 |
| FA24F | 146 ci | 3.7008" × 3.3858" | 10.6:1 | 260–271 |
| FA24DIT | 146 ci | 3.7008" × 3.3858" | — | 271 |
| FA24D | 145.7 ci | 3.7008" × 3.3858" | 12.5:1 | 228 |
| FA24F | 145.7 ci | 3.7008" × 3.3858" | 10.6:1 | 260–271 |
| FA · 3.386" × 3.386" · 12.5:1 | 122 ci | 3.3858" × 3.3858" | 12.5:1 | 200 |
| Fa20 Turbo | 122 ci | 3.3858" × 3.3858" | 10.6:1 | 268 |
| FA20DIT | 122 ci | 3.3858" × 3.3858" | — | 268 |
| FA · 3.386" × 3.386" · 10.6:1 | 121.9 ci | 3.3858" × 3.3858" | 10.6:1 | 250–300 |
| Fa20 D | 121.9 ci | 3.3858" × 3.3858" | 12.5:1 | 200 |
Stroke is constant at 3.3858" across the family — the displacement spread comes from bore, so these share a crank and differ in the block.
Compression spans 10.6:1 to 12.5:1, so fuel requirements differ meaningfully between members — worth checking before assuming parts interchange.
6 of 11 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.