See other engines in this family
Plymouth K specs: 360 ci (5.9L) 8-cylinder, 4.032 x 3.579 in (102.4 x 90.9 mm) bore and stroke, 8.4:1 compression. Rated 245 hp. Rod ratio and piston speed.
The Plymouth LA (K) is oversquare — the 4.0315" bore exceeds the 3.5787" stroke by 12.7% — a layout that favors airflow and RPM over leverage at the crank. The 3.5787" stroke puts mean piston speed at 4,000 ft/min around 6,700 RPM, which is where a production bottom end is generally considered at its limit. Each of the 8 cylinders displaces 45.0 ci (737 cc).
8.4:1 on iron heads is low by modern standards and generally happy on regular pump fuel.
It is one of 20 engines in the LA family, the largest at 360 ci. Factory fitments include the Plymouth Road Runner, Plymouth Duster, Plymouth Volaré and 2 others.
| Displacement | 360 ci / 5.9 L |
|---|---|
| Bore | 4.0315" |
| Stroke | 3.5787" |
| Cylinders | 8 |
| Compression ratio | 8.4:1 |
| Bore/stroke ratio | 1.127 |
| Block material | cast iron |
|---|---|
| Head material | cast iron |
| Valvetrain | OHV |
| Fuel type | gas |
| Advertised HP | 245 hp |
| Bore/stroke character | 1.127 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves |
|---|---|
| Mean piston speed at 6,000 RPM | 3,579 ft/min — in the range typical of performance street engines |
| Displacement per cylinder | 45.0 ci |
| Static compression | 8.4:1 — low by modern standards, generally happy on regular pump fuel |
Each link opens the calculator with this engine's specs already filled in.