See other engines in this family
The same engine also has a main page: Honda K-series 9.7:1.
Acura K24A specs: 2.4L (144 ci) 4-cylinder, 87 x 99 mm (3.4252 x 3.8976 in) bore and stroke, 9.7:1 compression. Rated 160 hp. Rod ratio and piston speed.
The Acura K24A is undersquare — the 3.8976" stroke exceeds the 3.4252" bore by 12.1% — a layout that trades peak RPM for leverage and torque low in the range. The 3.8976" stroke puts mean piston speed at 4,000 ft/min around 6,150 RPM, which is where a production bottom end is generally considered at its limit. Each of the 4 cylinders displaces 36.0 ci (590 cc).
9.7:1 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 8 engines in the Honda K-series family, the largest at 144 ci. Factory fitments include the Honda CR-V (RD5/RD6/RD7), Honda Element (YH1/YH2).
| Displacement | 144 ci / 2.4 L |
|---|---|
| Bore | 3.4252" |
| Stroke | 3.8976" |
| Cylinders | 4 |
| Compression ratio | 9.7:1 |
| Bore/stroke ratio | 0.879 |
| Block material | aluminum |
|---|---|
| Head material | aluminum |
| Valvetrain | DOHC |
| Fuel type | gas |
| Advertised HP | 160 hp |
| Bore/stroke character | 0.879 — undersquare — stroke exceeds bore, which favours low-end torque |
|---|---|
| Mean piston speed at 6,000 RPM | 3,898 ft/min — in the range typical of performance street engines |
| Displacement per cylinder | 36.0 ci |
| Static compression | 9.7:1 — in the range that usually runs on pump premium |
Each link opens the calculator with this engine's specs already filled in.