See other engines in this family
Cadillac V8 specs: 250 ci (4.1L) 8-cylinder, 3.465 x 3.307 in (88 x 84 mm) bore and stroke, 8.5:1 compression. Rated 135 hp. OHV. Rod ratio and piston speed.
The Cadillac HT4100 (V8) is close to square: 3.4646" bore against 3.3071" stroke, within 4.8%, which splits the difference between a high-revving layout and a torque layout. The 3.3071" stroke does not reach 4,000 ft/min of mean piston speed until about 7,250 RPM, so piston speed is not what limits this engine's revs — valvetrain and breathing are. Each of the 8 cylinders displaces 31.3 ci (512 cc).
8.5:1 on iron heads is low by modern standards and generally happy on regular pump fuel.
It is one of 3 engines in the HT4100 family, the smallest at 250 ci. Factory fitments include the Cadillac DeVille, Cadillac Eldorado, Cadillac Seville and 4 others.
| Displacement | 250 ci / 4.1 L |
|---|---|
| Bore | 3.4646" |
| Stroke | 3.3071" |
| Cylinders | 8 |
| Compression ratio | 8.5:1 |
| Bore/stroke ratio | 1.048 |
| Block material | aluminum |
|---|---|
| Head material | cast iron |
| Valvetrain | OHV |
| Fuel type | gas |
| Advertised HP | 135 hp |
| Bore/stroke character | 1.048 — square — bore and stroke are within 5%, a balanced compromise |
|---|---|
| Mean piston speed at 6,000 RPM | 3,307 ft/min — conservative for a street engine |
| Displacement per cylinder | 31.3 ci |
| Static compression | 8.5:1 — low by modern standards, generally happy on regular pump fuel |
Each link opens the calculator with this engine's specs already filled in.