EFI Prechamber Torch Ignition of Lean Mixtures

This paper describes the development of a prechamber-type torch ignition system on a modified 4-cyl, 140 cubic inch engine. The prechamber consists of a blind cavity coupled to the main chamber with an orifice. Fuel is supplied to the prechamber with an electronic fuel injector and this mixture is ignitied by a spark plug. The prechamber produces an ignition torch which ignites a main chamber that is supplied with a lean mixture carbureted in the conventional manner. The performance of this combustion concept was evaluated on the basis of vehicle drivability, exhaust emissions, and fuel economy in a 3000 lb weight class vehicle. /GMRL/