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The same engine also has a main page: Plymouth EGL.
Plymouth EGM specs: 230 ci (3.8L) 6-cylinder, 3.78 x 3.425 in (96 x 87 mm) bore and stroke, 9:1 compression. Rated 162 hp. OHV. Rod ratio and piston speed.
The Plymouth Chrysler EGA/EGB (EGM) is oversquare — the 3.7795" bore exceeds the 3.4252" stroke by 10.3% — a layout that favors airflow and RPM over leverage at the crank. The 3.4252" stroke puts mean piston speed at 4,000 ft/min around 7,000 RPM, which is where a production bottom end is generally considered at its limit. Each of the 6 cylinders displaces 38.3 ci (628 cc).
9:1 on aluminum heads is low by modern standards and generally happy on regular pump fuel.
It is one of 3 engines in the Chrysler EGA/EGB family, the largest at 230 ci. Factory fitments include the Plymouth Grand Voyager.
| Displacement | 230 ci / 3.8 L |
|---|---|
| Bore | 3.7795" |
| Stroke | 3.4252" |
| Cylinders | 6 |
| Compression ratio | 9:1 |
| Bore/stroke ratio | 1.103 |
| Block material | cast iron |
|---|---|
| Head material | aluminum |
| Valvetrain | OHV |
| Fuel type | gas |
| Advertised HP | 162 hp |
| Bore/stroke character | 1.103 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves |
|---|---|
| Mean piston speed at 6,000 RPM | 3,425 ft/min — conservative for a street engine |
| Displacement per cylinder | 38.3 ci |
| Static compression | 9:1 — low by modern standards, generally happy on regular pump fuel |
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