DI would indeed be 'the bomb'.   Hope Mazda picks up on this for the rotary
because a DIY injector port into the combustion chamber is not something for
the average home workshop!

Tracy

Wouldn't any injection after the exhaust port closed preclude, overlap affecting mileage?

 

A conventional injector(s) above the intake port would be in a cool low stress area.

 

Easy to do................

 

Injecting across the hot rotor face would get things atomized quickly.

 

No mass being added to the inducted air column. So curves in the intake tubes wouldn't screw things up quite so badly. 

 

Lynn E. Hanover

Lynn,

 I like the DI system for several reasons. Less charge contamination for better performance. Stratified charge possibilities. Lower pumping losses with a simpler intake, with or without a throttle valve. instant shutdown to prevent flooding. Possibly running leaner mixtures still to improve mileage. Multi fuel capability. Lastly injecting on the plug side to avoid the exhaust heat.

 

 The only cons I see to the system is the need to run a pump to feed high pressure to the injectors. The plumbing must handle HIGH common rail pressures of 1100 bar. Plumbing like this has been used on diesels for ages though and has become ultra reliable.  I think this is really the way to go. The other advantage is that with Audis, VWs, Mazdas, any other car manufacturers using this tech to build cars it will become available for less soon. Oh yea I believe Ford is using this system for all the new diesel pickup HD engines too. Give me a sanity check here. To me it looks very good.

 

For Tracy, I'm trying to find out what the pulse to the injector looks like I'll pass along any info.As I understand it the piezo injector is super fast in actuation. The talk is using multiple injection events per cycle to taylor the charge. My intent is to do a boss in the location Mazda used for the far trailing 3rd plug on the LeMans rotor housings. I already have a design layout for the injector boss that I believe is simpler than doing a p-port FWIW

 

Bill Jepson