Honda R engine

The Honda R engine is an inline-four engine launched in 2006 for the Honda Civic in its non-Si form. It is fuel injected, with an aluminium alloy block and head, a single overhead camshaft with sixteen valves, four per cylinder, and Honda's i-VTEC system, and it has a 10.5 to 1 compression ratio. A drive-by-wire throttle controlled by computer reduces pumping losses, and fuel-saving measures include ion-plated piston rings, plastic and aluminium parts, variable length intake manifolds and piston cooling jets. In the ninth-generation 1.8 litre Civic of 2012 to 2015 the pistons were treated with molybdenum disulfide. As of September 2019 the R series was offered only outside Japan.