American Motors 343ci specs: 4.08 x 3.28 in (103.6 x 83.3 mm) bore and stroke, shared by all 2 versions. Displacement, compression and factory ratings.
| Displacement | 343 ci |
|---|---|
| Cylinders | 8 |
| Bore | 4.080" |
| Stroke | 3.280" |
| Compression | 9.0–10.2:1 |
| Advertised power | 235–280 hp |
| Years | 1967–1969 |
| Cylinder head data | 2 of 2 engines |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| American Motors 343ci · 4.08" × 3.28" · 9:1 | 343 ci | 4.08" × 3.28" | 9:1 | 235 |
| American Motors 343ci · 4.08" × 3.28" · 10.2:1 | 343 ci | 4.08" × 3.28" | 10.2:1 | 280 |
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.