a method is presented for improving performance of direct injection spark ignition internal combustion engines at high load conditions by increasing the degree of homogeneity of the air - fuel mixture during the intake stroke of the engine . the improved performance is achieved by adding a deflector designed to reduce intake air impinging upon the fuel spray and deflecting it to the intake side of the combustion chamber , thus facilitating better fuel circulation throughout the combustion chamber . this method improves engine performance at high load engine operating conditions .