See other engines in this family
Cadillac L33 specs: 425 ci (7.0L) 8-cylinder, 4.083 x 4.059 in (103.7 x 103.1 mm) bore and stroke, 8.2:1 compression. Rated 180 hp, 1977–1979.
The Cadillac 425 Series (L33) is close to square: 4.0827" bore against 4.0591" stroke, within 0.6%, which splits the difference between a high-revving layout and a torque layout. The 4.0591" stroke puts mean piston speed at 4,000 ft/min around 5,900 RPM, which is where a production bottom end is generally considered at its limit. Each of the 8 cylinders displaces 53.1 ci (871 cc).
8.2:1 on iron heads is low by modern standards and generally happy on regular pump fuel.
It is one of 3 engines in the 425 Series family, all of them 425 ci — the differences between them are in compression, heads and rating, not displacement. 3 factory variants share these dimensions, rated at 180 hp across 1977–1979.
| Displacement | 425 ci / 7 L |
|---|---|
| Bore | 4.0827" |
| Stroke | 4.0591" |
| Cylinders | 8 |
| Configuration | V8 |
| Compression ratio | 8.2:1 * |
| Bore/stroke ratio | 1.006 |
* Compression ratio from a single source; not yet cross-verified.
| Block material | cast iron |
|---|---|
| Head material | cast iron |
| Valvetrain | OHV |
| Fuel type | gas |
| Firing order | 1-5-6-3-4-2-7-8 |
| Advertised HP | 180 hp |
| Years | 1977–1979 |
| Bore/stroke character | 1.006 — square — bore and stroke are within 5%, a balanced compromise |
|---|---|
| Mean piston speed at 6,000 RPM | 4,059 ft/min — in the range typical of performance street engines |
| Displacement per cylinder | 53.1 ci |
| Static compression | 8.2:1 — low by modern standards, generally happy on regular pump fuel |
Each link opens the calculator with this engine's specs already filled in.
These records share identical bore, stroke, displacement and compression. They differ by model year and factory power rating.
| Year | Advertised HP | Code |
|---|---|---|
| 1977 | 180 hp | L33 |
| 1978 | 180 hp | L33 |
| 1979 | 180 hp | L33 |
2 factory vehicles, 1977–1979. Each year opens that model's engine table.