I've never learnt about ignition systems so all of this could be fairly easy stuff.



The motor in question is a 12a twin dizzy bridgy. The dizzy's which came with the motor and have vacuum advance things(actuators??) attached to them and are obviously the standard item. A while ago I got a large box full of old parts for $20 and have been sifting through it. While sifting I found a set of dizzy's which are wired to ignitors and have no actuators or little arms in them. These are twin dizzy as they have 'L' and 'T' on them.



I thought that ignitors were used in electronic ignition? Could someone have jigged something up in the past? Wasn't S2 or 3 RX7 the elec igntion? I'm confused.



I can post pics if it would help the cause.



Thanks,

Nick

 

Pictures always help...

 

yep, thought i'd better. here's some pics... the dizzy on the left is the 'ignitor' one...

 

yep, thought i'd better. here's some pics... the dizzy on the left is the 'ignitor' one...

 

yep, thought i'd better. here's some pics... the dizzy on the left is the 'ignitor' one...

 

yep, thought i'd better. here's some pics... the dizzy on the left is the 'ignitor' one...





[attachment=28752:attachment][attachment=28753:attachment]



I should have taken the photo's on a higher res.



Nick

 

It looks like one dizzy has 4 teeth in the reluctor. How many does the other have? Man, if I had that setup, I'd go full direct fire leading and Trailing. Leading would have simultaneously firing late leading/wasted sparks. Trailing would just be single sparks per rotor face. Of course I have the extra parts and the know-how.



Please get back to us with more details and better pictures. Thanks.

 

i knew jeff would love this...

 

Ok, so i've just been trying to get my head around this whole ignition thing. So what you are saying Jeff is that you'd go for three coils? One each for the leading and a seperate one for both trailing? The coils are then wired directly to the plugs (direct fire)? Where do the ignitors come into this whole equation?



I checked both dizzy's and yes, they both have four teeth.



Cheers,

Nick

 

You could do it that way. The ignitor takes the signal from the variable reluctance sensor (pickup) and converts it into an on/off signal to trigger the coil. It;s nopt quite as simple as that because there are dwell timings involved etc, but that;s the basic idea.



My '73 12A has a '74 single dizzy front cover so I can use an '81-'85 dizzy, but if it still had the twin dizzy front cover, I'd figure out some sort of electronic direct fire ignition system, probably similar to what you've got there.