ION-related IGN Comments & Coil Quest

[David Chambers]

garfield at pilgrimhouse.com wrote:
> 
> Hey Maties.
> 
> I had a brain-flash (or fart, we'll see shortly) whilst looking over the
> DSE schematics for their CDI plans/article.
> 
> [SIDEBAR: the circuit and assembly is DIRT simple, and looks well thot
> out and done (true, the pc board is a disappointment cuz of it's size,
> but they wanted one you could do at home, I guess. Me I'd cram it in
> niceNtight on a piece of two-plane thru-hole 0.1" perf board), and the
> only "custom" part is really doable with anyone with two hands and half
> a brain-stem; it's the main inverter transformer, and the plans call out
> all the particulars and part nos. for the bobbin/core and other pieces
> from Philips you need to buy to assemble this "custom" transformer. The
> parts list is quite detailed in that respect; major kudos for that.
> Sooo, nuthin esoteric or hard about this one "custom" transformer.
> Sounds daunting but it's really a pieceOcake no-brainer.]
> 
> The guy's design (John Clarke...anyone on the list from Oz know him,
> BTW?) is for use with stock IGN coils. So while tryna think-out an ION
> circuit that doesn't need HV diodes, and still can use the stock coils,
> and having troubles seeing how that's EVER gonna be possible, the thot
> struck me... HEY, I'll ask all them bloaks on diy_efi if ANYONE has ever
> seen a so-called 4-terminal stock auto IGN coil? What I mean by that is,
> consider the normal IGN coils we're all used to. They're basically a
> 3-terminal device; one terminal is the HV output (the "top" of the
> secondary, if you will), and then there's a "shared/common" connection
> for both primary and the other side of the secondary, and then the third
> terminal, which is for the primary feed. So you essentially have what we
> used to call an auto-transformer, or a transformer with a common
> connection for both primary and secondary.
> 
> Now, what would be REALLY ideal for ION is a stock automotive IGN coil,
> but one that has it's primary and secondary completely independent (no
> common'd terminal), so you have a 4-terminal device, with three pins on
> the low voltage connector, and one for the HV secondary output.
> 
> So, there's the bottom line question, maties; anyone every seen such a
> beastie? I and my Napa pal went through our books and his inventory this
> afternoon, even called Echlin, but couldn't come up with anythin. Of
> course, we don't give a rip what shape or form it's in for eXperimental
> purposes, but I'd sure be grand if a real "in-situ" coil existed we
> could also use with the real ION. Ask around, see what you can come up
> with; I'm certain that IF such a beastie exists, sooner or later someone
> on the list will exhume it!
> 
> Meanwhile, I'm still slowly working on my "patent commentary" and
> example circuits, so it's comin.
> 
> Hey, BTW, I had another somewhat bizarre thot, incase we CAN'T find such
> a coil to play with, that even with box stock IGN systems, and NO mods,
> one could actually build some lil adapter blocks that went between the
> HV lead and the plug top, and using some few HV diodes (there's nuthin
> wrong with them, BTW, they're robust and failsoft, it's just that I'm
> stuck on being able to do the "elegance" thang like Saab did, where THEY
> don't need any atoll), you could ADD the ionization detection into an
> existing IGN system, on a per-plug basis. I see absolutely nuthin that
> would prevent this, EXCEPT we still don't know if the longer spark
> duration of inductive IGN is gonna "blank" critical portions of the IGN
> phase. But, yeah, even the idea that MikeMorrin suggested might be
> possible, in that these "inserted measurement blocks" could actually
> quench the "tail" of the inductive spark early and MAKE a window for ION
> to do it's measurement magic. That too might be possible.
> 
> I only mention this possibility because IF we could make this work, if
> only for eXperimental purposes, it would allow dyno tuners and others to
> LEAVE their acoustic knock detectors on the engine, and COMPARE the
> "indicator and measurement" functionality of one vrs the other, and
> REALLY determine if ION is giving you anything back. The reason I
> mention dyno tuners in particular is they have the easiest time in
> dialing in a forced "knock" on command. The rest of us have to tweak
> timing manually, and be careful we don't overdo it with load and
> throttle. I know there are several guys on the list that could do this
> comparison, so this too is another avenue of eXperimentation. Here, I
> don't think the "ionization circuit" per se is the
> difficult/questionable part, but rather what to do with the stock
> inductive IGN system's spark duration.
> 
> Thas all fer now. Scan yer personal archives and see if you've ever seen
> a "4-terminal" IGN coil. Any feedback appreciated.
> 
> Gar
Not quite what you where thinking of but, how about using a dual plug
coil pack and using one of the plug outputs as your secondary ground.
You then get the two inputs for the primary and the secondary winding on
the two plug leads?
David