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The same engine also has a main page: Chevrolet LE5.
GMC Ecotec I4 specs: 145 ci (2.4L) 4-cylinder, 3.465 x 3.858 in (88 x 98 mm) bore and stroke, 10.4:1 compression. Rated 177-180 hp. DOHC.
The GMC Ecotec I4 is undersquare — the 3.8583" stroke exceeds the 3.4646" bore by 10.2% — a layout that trades peak RPM for leverage and torque low in the range. The 3.8583" stroke puts mean piston speed at 4,000 ft/min around 6,200 RPM, which is where a production bottom end is generally considered at its limit. Each of the 4 cylinders displaces 36.3 ci (594 cc).
10.4:1 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 6 engines in the Ecotec I4 family, the largest at 145 ci. 2 factory variants share these dimensions, rated from 177 to 180 hp. Factory fitments include the Chevrolet Cobalt SS, Pontiac G6, Saturn Sky and 4 others.
| Displacement | 145 ci / 2.4 L |
|---|---|
| Bore | 3.4646" |
| Stroke | 3.8583" |
| Cylinders | 4 |
| Compression ratio | 10.4:1 |
| Bore/stroke ratio | 0.898 |
| Block material | aluminum |
|---|---|
| Head material | aluminum |
| Valvetrain | DOHC |
| Fuel type | gas |
| Advertised HP | 177–180 hp |
| Bore/stroke character | 0.898 — undersquare — stroke exceeds bore, which favours low-end torque |
|---|---|
| Mean piston speed at 6,000 RPM | 3,858 ft/min — in the range typical of performance street engines |
| Displacement per cylinder | 36.3 ci |
| Static compression | 10.4:1 — 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 |
|---|---|---|
| — | 177 hp | LE5 |
| — | 180 hp | LE9 |