See other engines in this family
Honda R-series (2006–2022) specs: 1.8L (109.8 ci) 4-cylinder, 81 x 87.3 mm (3.1890 x 3.4370 in) bore and stroke. Rated 113-141 hp, 2006–2022.
The Honda R-series (2006–2022) is undersquare — the 3.437" stroke exceeds the 3.189" bore by 7.2% — a layout that trades peak RPM for leverage and torque low in the range. The 3.437" 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 4 cylinders displaces 27.5 ci (450 cc).
It is one of 4 engines in the R-series family, all of them 109.8 ci — the differences between them are in compression, heads and rating, not displacement. 13 factory variants share these dimensions, rated from 113 to 141 hp across 2006–2022.
| Displacement | 109.8 ci / 1.8 L |
|---|---|
| Bore | 3.189" |
| Stroke | 3.437" |
| Cylinders | 4 |
| Configuration | I4 |
| Compression ratio | 10.6–12.5:1 (published figures vary) |
| Bore/stroke ratio | 0.928 |
| Valvetrain | SOHC |
|---|---|
| Fuel type | gas |
| Advertised HP | 113–141 hp |
| Years | 2006–2022 |
| Year | Version | HP @ rpm | Torque @ rpm | Comp. |
|---|---|---|---|---|
| 2006 | net | 113 @ 6300 | 109 lb-ft @ 4300 | 12.5:1 |
| 2007 | net | 113 @ 6300 | 109 lb-ft @ 4300 | 12.5:1 |
| 2008 | net | 113 @ 6300 | 109 lb-ft @ 4300 | 12.5:1 |
| 2009 | net | 113 @ 6300 | 109 lb-ft @ 4300 | 12.5:1 |
| 2010 | net | 113 @ 6300 | 109 lb-ft @ 4300 | 12.5:1 |
| 2011 | net | 113 @ 6300 | 109 lb-ft @ 4300 | 12.5:1 |
| 2016 | net | 141 @ 6500 | 127 lb-ft @ 4300 | 10.6:1 |
| 2017 | net | 141 @ 6500 | 127 lb-ft @ 4300 | 10.6:1 |
| 2018 | net | 141 @ 6500 | 127 lb-ft @ 4300 | 10.6:1 |
| 2019 | net | 141 @ 6500 | 127 lb-ft @ 4300 | 10.6:1 |
| 2020 | net | 141 @ 6500 | 127 lb-ft @ 4300 | 10.6:1 |
| 2021 | net | 141 @ 6500 | 127 lb-ft @ 4300 | 10.6:1 |
| 2022 | net | 141 @ 6500 | 127 lb-ft @ 4300 | 10.6:1 |
Factory specification sheet.
| Bore/stroke character | 0.928 — undersquare — stroke exceeds bore, which favours low-end torque |
|---|---|
| Mean piston speed at 6,000 RPM | 3,437 ft/min — conservative for a street engine |
| Displacement per cylinder | 27.4 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 |
|---|---|---|
| 2006 | 113 hp | — |
| 2007 | 113 hp | — |
| 2008 | 113 hp | — |
| 2009 | 113 hp | — |
| 2010 | 113 hp | — |
| 2011 | 113 hp | — |
| 2016 | 141 hp | — |
| 2017 | 141 hp | — |
| 2018 | 141 hp | — |
| 2019 | 141 hp | — |
| 2020 | 141 hp | — |
| 2021 | 141 hp | — |
| 2022 | 141 hp | — |
2 factory vehicles, 2006–2022. Each year opens that model's engine table.