Bore, stroke, displacement and compression for all 11 Nissan RB engines, compared side by side. Plus rod ratio and head specs where published.
| Displacement | 121.8–182.7 ci |
|---|---|
| Cylinders | 6 |
| Bore | 3.071–3.386" |
| Stroke | 2.744–3.346" |
| Compression | 7.8–10.5:1 |
| Advertised power | 128–276 hp |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| RB30E | 182.7 ci | 3.3858" × 3.3465" | 9:1 | 155 |
| RB30ET | 182.7 ci | 3.3858" × 3.3465" | 7.8:1 | 201 |
| RB30DE | 182.7 ci | 3.3858" × 3.3465" | 10:1 | 227 |
| RB30DETT | 182.7 ci | 3.3858" × 3.3465" | 8.5:1 | — |
| RB26DETT | 158.5 ci | 3.3858" × 2.9016" | 8.5:1 | 276 |
| RB25DE | 152.4 ci | 3.3858" × 2.8228" | 10:1 | 178 |
| RB · 3.386" × 2.823" · 9:1 | 152.4 ci | 3.3858" × 2.8228" | 9:1 | 245–276 |
| RB25DE NEO | 152.4 ci | 3.3858" × 2.8228" | 10.5:1 | 197 |
| RB24S | 146.5 ci | 3.3858" × 2.7441" | 9:1 | 139 |
| RB · 3.071" × 2.744" · 9.5:1 | 121.8 ci | 3.0709" × 2.7441" | 9.5:1 | 128–153 |
| RB · 3.071" × 2.744" · 8.5:1 | 121.8 ci | 3.0709" × 2.7441" | 8.5:1 | 168–212 |
Both bore and stroke vary across the family, so these are separate castings rather than variations on one block.
Compression spans 7.8:1 to 10.5:1, so fuel requirements differ meaningfully between members — worth checking before assuming parts interchange.
7 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.