See other engines in this family
Hyundai G4CR specs: 1.3L (79.3 ci) 4-cylinder, 71.5 x 82 mm (2.8150 x 3.2283 in) bore and stroke, 9.4:1 compression. Rated 72 hp. Rod ratio and piston speed.
The Hyundai G4CR is undersquare — the 3.2283" stroke exceeds the 2.815" bore by 12.8% — a layout that trades peak RPM for leverage and torque low in the range. The 3.2283" stroke does not reach 4,000 ft/min of mean piston speed until about 7,450 RPM, so piston speed is not what limits this engine's revs — valvetrain and breathing are. Each of the 4 cylinders displaces 19.8 ci (325 cc).
9.4:1 on aluminum heads is low by modern standards and generally happy on regular pump fuel.
It is one of 2 engines in the Orion family, the smallest at 79.3 ci. Factory fitments include the Hyundai Accent.
| Displacement | 79.3 ci / 1.3 L |
|---|---|
| Bore | 2.815" |
| Stroke | 3.2283" |
| Cylinders | 4 |
| Compression ratio | 9.4:1 |
| Bore/stroke ratio | 0.872 |
| Block material | cast iron |
|---|---|
| Head material | aluminum |
| Valvetrain | SOHC |
| Fuel type | gas |
| Advertised HP | 72 hp |
| Bore/stroke character | 0.872 — undersquare — stroke exceeds bore, which favours low-end torque |
|---|---|
| Mean piston speed at 6,000 RPM | 3,228 ft/min — conservative for a street engine |
| Displacement per cylinder | 19.8 ci |
| Static compression | 9.4:1 — low by modern standards, generally happy on regular pump fuel |
Each link opens the calculator with this engine's specs already filled in.