Bore, stroke, displacement and compression for all 4 Cadillac OHV V8 engines, compared side by side. Plus rod ratio and head specs where published.
| Displacement | 390–500 ci |
|---|---|
| Cylinders | 8 |
| Bore | 4.000–4.300" |
| Stroke | 3.752–4.304" |
| Compression | 8.5–10.5:1 |
| Advertised power | 325–400 hp |
| Engine | Displacement | Bore × Stroke | CR | HP |
|---|---|---|---|---|
| 500 | 500 ci | 4.3" × 4.304" | 8.5:1 | 400 |
| 472 | 472 ci | 4.2992" × 4.0591" | 10:1 | 375 |
| 429 | 429 ci | 4.25" × 3.752" | 10.5:1 | 340 |
| 390 | 390 ci | 4" × 3.875" | 10.5:1 | 325 |
Both bore and stroke vary across the family, so these are separate castings rather than variations on one block.
Compression spans 8.5:1 to 10.5:1, so fuel requirements differ meaningfully between members — worth checking before assuming parts interchange.
2 of 4 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.