oi8228oi said:
While I was totally unaware that gasser DI technology had hit production in the US, I have been aware of DI gasser technology for a couple years, now. It works in more or less the same way that DI diesel injection works, only it still has a spark plug.
It allows for higher compression ratios, higher boost from super/turbochargers, etc, without detonation (pre-ignition). Since the injection event dictates timing, the fuel cannot pre-ignite, since it will not be injected until it is supposed to ignite.
Many DI gasser theories also include elimination of the throttle plate, which will boost partial-throttle efficiency.
This is also called "lean burn" technology, and I hope it is becoming the wave of the future. Think fuel economy like a diesel, with great horsepower.
As of yet, emissions has kept DI gasser technology from the market, since the way a 3-way catalyst works relies on the engine being at or near stochiometric (in fact, alternating back and forth from rich to lean) This is because, of the 3-"ways" inside the catalyst, one of them relies on a rich burn (anaerobic), while the other two rely on a lean burn (aerobic), to accomplish their tasks. In DI gasser tech (as in diesel tech) the rig almost exclusively runs lean (unless it is puking black smoke, then it is rich...) and therefore eliminates the 3rd "way" from working properly. This is the "way" that eliminates NOx, so "lean burn" rigs create lots of untreatable NOx (includes both gasser and diesel).
To fix this problem, they have to EGR the ever loving crap out of them. In fact, some new DI systems include ports in the head to "swirl" EGR gasses around the outside of the charge, to create a more efficient NOx-block.
Anyway, hope this helps. I have no idea if this is indeed what this Mazda rig actually is or not, but I can't imagine that they can advertise DI if it is really not.
