Patent ID: 8146555

Claim:
A direct-injection spark-ignition system, comprising: a fuel injector configured to provide fuel to a combustion chamber of an internal combustion engine; and a spark plug having a longitudinal first axis and configured to ignite the fuel provided by the fuel injector, the spark plug comprising a center electrode substantially aligned with the longitudinal first axis, a surface-gap ground electrode radially aligned with the center electrode along a surface-gap electrode second axis substantially orthogonal to the longitudinal first axis and passing therethrough, the center electrode and the surface-gap ground electrode defining a radial spark gap therebetween, and a J-gap ground electrode radially aligned with the center electrode, the center electrode and the J-gap ground electrode defining an axial spark gap therebetween, said J-gap ground electrode radial alignment having an angular separation from said surface-gap electrode second axis of no greater than about 30 degrees, wherein the fuel injector is aligned within 20 degrees of said surface-gap electrode second axis.