Bore, stroke, displacement and compression for all 2 Saturn Ecotec engines, compared side by side. Plus rod ratio and head specs where published.
| Displacement | 122–134 ci |
|---|---|
| Cylinders | 4 |
| Bore | 3.386" |
| Stroke | 3.386–3.724" |
| Compression | 9.5–10.0:1 |
| Advertised power | 135–205 hp |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| L61 | 134 ci | 3.3858" × 3.7244" | 10:1 | 135 |
| LSJ | 122 ci | 3.3858" × 3.3858" | 9.5:1 | 205 |
Every engine here shares a 3.3858" bore; displacement varies by stroke alone, which is the signature of a family built on one block with different cranks.
1 of 2 are undersquare — stroke larger than bore, favouring torque low in the range.
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.