As automakers continue their quest for more power AND more efficiency AND lower emissions, the gasoline engine and the diesel engine are growing closer, adopting tricks from one another.
One thing the gas engine has cribbed is to spray the fuel directly into the combustion chamber at high pressure rather than introducing it to the intake charge (where some of it coated the backside of the intake valve and evaporated).
BMW once broke down the power increase of each component changed when they moved from the M52TU to M54 engine family in 2001, but no one had released how much power and efficiency D.I. gives in and of itself til now because it was bundle with other changes such as turbocharging or a radically different motor.
Rather than forced induction or hot rodding the motor as is the norm, Cadillac’s next CTS will have an optional engine that simply adds direct injection to the existing 3.6L. The resut is an 15% increase in power, an 8% increase in torque and a 25% decrease in hydrocarbon emissions.
Given that everything coming out of GM these days uses the high feature 3.6, I’d expect that sometime down the road the technology will trickle down through the lineup.
Looks like the loud ticking that you hear at idle is here to stay.