See other engines in this family
The same engine also has a main page: Lincoln InTech 10.5:1.
Lincoln Modular InTech specs: 238 ci (3.9L) 8-cylinder, 3.386 x 3.307 in (86 x 84 mm) bore and stroke, 10.5:1 compression. Rated 252-280 hp. DOHC.
The Lincoln Modular InTech is close to square: 3.3858" bore against 3.3071" stroke, within 2.4%, 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 29.8 ci (488 cc).
10.5:1 on aluminum heads is in the range that usually runs on pump premium; aluminum sheds heat faster than iron, which makes the same number a little more forgiving.
It is one of 3 engines in the Modular InTech family, the smallest at 238 ci. 2 factory variants share these dimensions, rated from 252 to 280 hp. Factory fitments include the Lincoln LS.
| Displacement | 238 ci / 3.9 L |
|---|---|
| Bore | 3.3858" |
| Stroke | 3.3071" |
| Cylinders | 8 |
| Compression ratio | 10.5:1 |
| Bore/stroke ratio | 1.024 |
| Block material | aluminum |
|---|---|
| Head material | aluminum |
| Valvetrain | DOHC |
| Fuel type | gas |
| Advertised HP | 252–280 hp |
| Bore/stroke character | 1.024 — 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 | 29.8 ci |
| Static compression | 10.5:1 — in the range that usually runs on pump premium |
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 |
|---|---|---|
| — | 252 hp | 3.9 DOHC |
| — | 280 hp | 3.9 DOHC VVT |