Multi-valve

A multi-valve or multivalve four-stroke internal combustion engine is one where each cylinder has more than two valves – more than the minimum required of one of each, for the purposes of air and fuel intake, and venting exhaust gases. Multi-valve engines were conceived to improve one or both of these, often called "better breathing", and with the added benefit of more valves that are smaller, thus having less mass in motion (per individual valve and spring), may also be able to operate at higher revolutions per minute (RPM) than a two-valve engine, delivering even more intake an/or exhaust per unit of time, thus potentially more power.