Information on smaller nonroad spark-ignition engines is on the Lawn and Garden (small gasoline equipment) page.

In spark-ignition (petrol-type) engines all gas fuels have a lot to offer, and natural gas produces the cleanest burn of the lot.

In the type of gasoline spark-ignition engines that are dominant in the United States market, fuel and air are mixed before entering the engine cylinder.

Akroyd-Stuart's heavy oil engine (compared to spark-ignition) is distinctly different from Rudolf Diesel's better-known engine where ignition is initiated through the heat of compression.

Akroyd-Stuart's compression ignition engine (as opposed to spark-ignition) was patented two years earlier than Diesel's similar engine; Diesel's patentable idea was to increase the pressure.

Emission Standards for Forklifts, Generators, and Compressors Covers information on controlling emissions from non-road spark-ignition (si) engines over 19 KW (25 hp).

Predictive combustion simulations for "downsized" direct injection spark-ignition engines: solutions for pre-ignition ("mega-knock"), misfire, extinction, flame propagation and conventional "knock", cmcl innovations, accessed June 2010.

Neal, Robert J.; Packard as an Aero Engine Builder - Spark-Ignition Engines: 1923-1939 Torque Meter Vol.

The term spark-ignition engine refers to internal combustion engines, usually petrol engines, where the combustion process of the air-fuel mixture is ignited by a spark from a spark plug.

A petrol engine (known as a gasoline engine in North America) is an internal combustion engine with spark-ignition, designed to run on petrol (gasoline) and similar volatile fuels.

By the late 1930s, serious craftsmen/hobbyists were racing relatively large (1:16 - 1:18 scale) model cars powered by small internal combustion engines, originally with spark-ignition, later with glow plug engines.

This page provides regulations and guidance documents for nonroad spark-ignition (SI) engines over 19 kW (25 horsepower), including many kinds of equipment, such as forklifts, generators, and many other farm, industrial and construction applications.

G M Abu-Orf and R S Cant, "A Turbulent Reaction Rate Model for Premixed Turbulent Combustion in Spark-Ignition Engines" Combustion & Flame, 122 233-252 (2000)

The rule regulates exhaust emissions from new spark-ignition (SI) gasoline marine engines including outboard engines, personal watercraft engines and jet boat engines beginning with the 1998 model year and the rule is fully phased-in by the 2006 model year.