Mazda to make gasoline engines without spark plugs. 18 to 1 compression ratio.

Heard last night Mazda to make gasoline engines with no spark plugs. Supposed to be almost as fuel efficient as a Diesel engine.

 

Direct injection makes it possible.

 

Makes sense. Since all Diesels if I'm not mistaken have fuel injected directly into the cylinder.

 

Will it need DEF? I would think NOX emissions would be quite high.

 

Why would it be any higher than usual? It's 30% more efficient. Are you saying that comes at the cost of more nox?

 

Makes sense. The motor is going to get a much more complete burn of the fuel charge with this high pressure ignition system and NOX emissions are the byproduct of a completely exhausted fuel cycle, so there would, theoretically speaking, be more NOX emissions.

 

Sweet find OP! Thanks for sharing

 

Run lean and away from the stoichiometric 14.7-1 ratio and NOX levels go up. I believe honda had had that issue years ago in some of their high fuel economy cars. [and why they can't even get the MPG they used to get in their small cars] They could run lean for better MPG but emissions NOX wouldn't pass. It's one of the problems about why we don't have vehicles that get higher MPG. We can get them to higher MPG, we just can't get them to pass NOX emission mandated levels when we do.

 

Thus article is wrong. They still have plugs. They just don't use them all the time.

 

I'm still curious if mazda solved their rotary reliability issues (e.g. Seals). This killed the rx8.

 

Nope. That was a beast to get to pass emissions too.

One of the few engines you really needed a tach to know how fast it was spinning.

 

The fix was an LS swap.

 

I've just now been reading about this in the news. You would think they'd have solved the problem before coming out with plans to mass produce in 2019.