CDI's in Oz

[Bruce Plecan]

From: Mike Morrin <mikem at southern.co.nz>
Subject: Re: CDI's in Oz


>>I wouldn't recommend any CDI for a modern 4 cycle engine.
>>Ehh? Wow, what about the SAAB system we've been discussing, which has
>>been in the field with nary a single design change, since '92?
>>Whadamy missin here, Mike?
>>
>I must learn not to make throwaway comments...
>Just the reason of CDI sparks being too fast for lean burning motors.
>Typically causing a light throttle misfire.
>CDI apparently needs either a rich mixture, or a combustion chamber design
>which ensures that there is plenty of gas near the spark gap at the time of
>ignition.
>I don't know whether Saab have a way of stretching the spark (the DSE kit
>doesn't), or if they just have an engine design which tolerates short spark
>duration.
>regards,
>Mike Morrin


Sounds exactly what Dr Jacobs called in his book "Punch Through"
Such a high level of ionazation happening so fast that the spark
occurs, and little or no reaction occurs.
  Interestingly enough as I recall, (can't find the patent no.) his patent
on this is about how he turns off the cap.s discharge..
  Cheers
Bruce