See other engines in this family
Pontiac LA1 specs: 207 ci (3.4L) 6-cylinder, 3.622 x 3.307 in (92 x 84 mm) bore and stroke, 9.5:1 compression. Rated 175 hp, 2000–2003.
The Pontiac 207ci (LA1) is oversquare — the 3.622" bore exceeds the 3.3071" stroke by 9.5% — a layout that favors airflow and RPM over leverage at the crank. 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 6 cylinders displaces 34.5 ci (565 cc).
9.5:1 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 5 engines in the Pontiac 207ci family, the largest at 207 ci. 4 factory variants share these dimensions, rated at 175 hp across 2000–2003.
| Displacement | 207 ci / 3.4 L |
|---|---|
| Bore | 3.622" |
| Stroke | 3.3071" |
| Cylinders | 6 |
| Configuration | V6 |
| Compression ratio | 9.5:1 * |
| Bore/stroke ratio | 1.095 |
* Compression ratio from a single source; not yet cross-verified.
| Block material | cast iron |
|---|---|
| Head material | aluminum |
| Valvetrain | OHV |
| Fuel type | gas |
| Advertised HP | 175 hp |
| Years | 2000–2003 |
| Bore/stroke character | 1.095 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves |
|---|---|
| Mean piston speed at 6,000 RPM | 3,307 ft/min — conservative for a street engine |
| Displacement per cylinder | 34.5 ci |
| Static compression | 9.5:1 — 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 |
|---|---|---|
| 2000 | 175 hp | LA1 |
| 2001 | 175 hp | LA1 |
| 2002 | 175 hp | LA1 |
| 2003 | 175 hp | LA1 |
3 factory vehicles, 1999–2005. Each year opens that model's engine table.