See other engines in this family
Ram EZH specs: 345 ci (5.7L) 8-cylinder, 3.917 x 3.579 in (99.5 x 90.9 mm) bore and stroke. Rated 370-376 hp, 2011–2023. Used in the Dodge Challenger. OHV.
The Ram Hemi (EZH) is oversquare — the 3.9173" bore exceeds the 3.5787" stroke by 9.5% — 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 43.1 ci (707 cc).
It is one of 10 engines in the Hemi family, the smallest at 345 ci. 26 factory variants share these dimensions, rated from 370 to 376 hp across 2011–2023.
| Displacement | 345 ci / 5.7 L |
|---|---|
| Bore | 3.9173" |
| Stroke | 3.5787" |
| Cylinders | 8 |
| Configuration | V8 |
| Bore/stroke ratio | 1.095 |
| Block material | cast iron |
|---|---|
| Head material | aluminum |
| Valvetrain | OHV |
| Fuel type | gas |
| Advertised HP | 370–376 hp |
| Years | 2011–2023 |
| Bore/stroke character | 1.095 — 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 | 43.1 ci |
Each link opens the calculator with this engine's specs already filled in.
These records share identical bore, stroke, displacement and compression. They differ by model year and factory power rating.
| Year | Advertised HP | Code |
|---|---|---|
| 2011 | 370 hp | EZH |
| 2011 | 376 hp | EZH |
| 2012 | 370 hp | EZH |
| 2012 | 375 hp | EZH |
| 2013 | 370 hp | EZH |
| 2013 | 375 hp | EZH |
| 2014 | 370 hp | EZH |
| 2014 | 375 hp | EZH |
| 2015 | 370 hp | EZH |
| 2015 | 375 hp | EZH |
| 2016 | 370 hp | EZH |
| 2016 | 375 hp | EZH |
| 2017 | 370 hp | EZH |
| 2017 | 375 hp | EZH |
| 2018 | 370 hp | EZH |
| 2018 | 375 hp | EZH |
| 2019 | 370 hp | EZH |
| 2019 | 375 hp | EZH |
| 2020 | 370 hp | EZH |
| 2020 | 375 hp | EZH |
| 2021 | 370 hp | EZH |
| 2021 | 375 hp | EZH |
| 2022 | 370 hp | EZH |
| 2022 | 375 hp | EZH |
| 2023 | 370 hp | EZH |
| 2023 | 375 hp | EZH |