An internal combustion engine having a main combustion chamber, a first prechamber, a second prechamber, a first ignition plug and a second ignition plug. The main combustion chamber is in fluid communication with a first prechamber and a second prechamber. The first ignition plug is disposed in the first prechamber for igniting a charge in the first prechamber to form a first flame jet directed into the main combustion chamber. The second ignition plug disposed in the second prechamber for igniting a charge in the second prechamber to form a second flame jet directed into the main combustion chamber. The first flame jet and the second flame jet overlap in the main combustion chamber.

In one embodiment, a combustion system for an engine is disclosed. The system includes a cylinder block that defines a cylinder bore and opposing pre-chambers located along a circumference of the cylinder bore. The system also includes a fuel injector located equidistant from the circumference of the cylinder bore that injects fuel in a direction perpendicular to a diameter of the cylinder bore. The system further includes a piston located within the cylinder bore that has a substantially conically shaped crown having fuel direction grooves that direct the fuel from the fuel injector towards the opposing pre-chambers.

Systems, devices, and methods described herein provide one or more radical chemicals generators (RCGs) and/or mini-chambers (M-Cs) that can be used to provide enhanced radical ignition (ERI) in an internal combustion engine. RCGs as described herein can include quenching systems (QSs) that can be configured to quench a flame of combustion products to produce a jet of partial combustion products containing radical species (RS). The jet of partial combustion products can be injected to a main combustion chamber (MCC) of an engine to induce ERI. ERI can proceed under leaner fuel conditions and lower temperatures compared to those needed for conventional thermally induced, fuel oxidation chain initiation reaction processes.