They can control and modulate the injection far more with DI, because they&#x27;re not limited to intake injection. I cannot give you much in the way of credible sources on the 50% claim from DI, only that I&#x27;ve read it from multiple sources - so treat it as marketing speak.<p>But even if we&#x27;re &quot;only&quot; gaining 5% efficiency from DI, it&#x27;s a pretty big deal. I&#x27;m fairly sure a GP3 or GP2 engine supplier have stated that DI provides better mileage, power, and torque, especially with an FI engine, compared to MPI.