rx7turbo1

I was looking at some of the animations on http://www.rotaryengineillustrated.com/ and noticed something I've never noticed before...The trailing plug seems to fire a third spark at the end of the power stroke, just before the apex seal passes the plugs... is this only done for emissions reasons? Whoudl you considered this a waste spark?

The reason I bring this up is b/c a lot of us run stand-alone systems that, as far as I know, cannot support this second trailing spark. Do you think we are all just creating more emissions? or possibly losing out on potential power? Bigger flames if anything?

This also brings up another question I had. What is the reason for the third spark plug that you sometimes see on mazda's race motors? Is this something we should be looking into? The problem would be controlling this type of ignition. Maybe this third plug is replacing whats going on above?

Any help would be greatly appreciated. I'd like to understand this ignition stuff

maxcooper

Since the leading plugs share a coil on the stock ignition system, there is a wasted spark for the leading plugs. However, I am not aware of any wasted spark coming from the trailing plugs on the stock ignition system.

-Max

fast13b

Remember that the leading plug is the bottom one. It fires twice per combustion while the trailing fires once.

HAILERS

I think the second spark of the SAME LEAD plug in that animation is something called a MISTAKE. I'm not refering to the wasted lead spark on the other rotor, just the same lead plug firing twice in that combustion sequence shown on the video.