See other engines in this family
GMC LK5 specs: 169 ci (2.8L) 4-cylinder, 3.661 x 4.016 in (93 x 102 mm) bore and stroke, 10.1:1 compression. Rated 175 hp. DOHC. Rod ratio and piston speed.
The GMC Vortec 2800 (2.8L I4) (LK5) is undersquare — the 4.0157" stroke exceeds the 3.6614" bore by 8.8% — a layout that trades peak RPM for leverage and torque low in the range. The 4.0157" stroke puts mean piston speed at 4,000 ft/min around 6,000 RPM, which is where a production bottom end is generally considered at its limit. Each of the 4 cylinders displaces 42.3 ci (692 cc).
10.1:1 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.
Factory fitments include the GMC Canyon, Chevrolet Colorado, Isuzu i-280.
| Displacement | 169 ci / 2.8 L |
|---|---|
| Bore | 3.6614" |
| Stroke | 4.0157" |
| Cylinders | 4 |
| Compression ratio | 10.1:1 |
| Bore/stroke ratio | 0.912 |
| Block material | aluminum |
|---|---|
| Head material | aluminum |
| Valvetrain | DOHC |
| Fuel type | gas |
| Advertised HP | 175 hp |
| Bore/stroke character | 0.912 — undersquare — stroke exceeds bore, which favours low-end torque |
|---|---|
| Mean piston speed at 6,000 RPM | 4,016 ft/min — in the range typical of performance street engines |
| Displacement per cylinder | 42.3 ci |
| Static compression | 10.1:1 — in the range that usually runs on pump premium |
Each link opens the calculator with this engine's specs already filled in.