Twin-plugging with standard dizzy

JohnJL · 07-07-2005, 03:45 PM

I've been doin some research and it seems the 12-lead dizzy caps are unobtanium. Am monitoring the site for BURN-BROS' rotor prototype, not sure it will work in my 3.0 dizzy though.

Anyway...is there a way to retain the standard dizzy for signal purposes, sending the signal to an ignition control (MSII), then along to a coil(s), and finally to the plugs? Can the dizzy terminals be connected to a "connection board" with two output connections for each cylinder, thereby splitting the hot side of the coils and firing the two cylinders off the rotor/dizzy?
I'm basically looking to retain my dizzy if possible, use MSII for ignition control, and avoid the expense of either Electromotive coils or 12-plug Porsche caps.

john

Formerly Steve Wilkinson · 07-07-2005, 04:17 PM

I frankly don't remember what I paid for it, but it was hardly unobtanium when I sent my standard distributor to Steve Weiner, at Rennsport Systems, in Portland (Oregon) and had him modify it to run a 12-plug cap to a pair of Blaster coils and two MSD 6AL units to fire the twin-plug heads he'd machined for me. Not a big deal. Steve is at porsche@rennsportsystems.com, and he'll set you up just fine.

Stephan

randywebb · 07-07-2005, 05:34 PM

most modify a 964/993 distributor -- not cheap but a lot less than the cap for the 12 plug dist. that PAG used.

it would be nice if something lighter, cheaper, and more reliable existed...

Steve@Rennsport · 07-07-2005, 05:39 PM

Quote:

Originally posted by randywebb
most modify a 964/993 distributor -- not cheap but a lot less than the cap for the 12 plug dist. that PAG used.

it would be nice if something lighter, cheaper, and more reliable existed...

More options are becoming available as I speak, LOL, but IMHO the 3.6 dual-distributor is still the cheapest way to do this if budget is the overriding criteria.

tctnd · 07-07-2005, 08:08 PM

I don't know if anyones tried this but it should be possible to put an inductive pickup on each of the existing outputs (plug wires) and use the signal to trigger inexpensive Ford or GM coil packs for a second plug (or a third, forth....). The Porsche twin dizzy with belt really seems like a stone age solution.
regards,
Phil

randywebb · 07-07-2005, 08:32 PM

"More options are becoming available as I speak"
- keep us posted!

The dual ones add 5.4 lbs. to the very rear of the car (plus I don't like the way it looks...)

starlifter1 · 07-07-2005, 08:35 PM

Is there a good place to find these 964/993 dizzys

randywebb · 07-07-2005, 08:42 PM

Find a 993 with the engine lid unlocked.... or just hoist the whole thing into your plane...

I got mine from Okla. Foreign - other used parts places will have them too. Or eBay. You also need an SC distr. You take the guts out of the SC one and implant it into the 3.6L one. I don't know the details as a machinist did that for mine.

JohnJL · 07-08-2005, 02:58 PM

Thanks for the feedback, but this is getting off-track. I want to keep my dizzy for engine position sensing, my question was has anyone gotten creative with adapting the dixxy terminals into two each, or another idea?

JohnJL · 07-08-2005, 03:24 PM

Would this work?

1. Would 1 coil be enough to fire both plugs?
2. Could I wire up 2 coils in series or otherwise to get huge power through to fire both plugs? or
3. WOuld it just end up firing one plug in each cylinder, whichever happened to arc first, all voltage would jump across that one?

Formerly Steve Wilkinson · 07-08-2005, 03:27 PM

Basically, you simply can't fire two plugs from a single source, i.e. a single rotor post, no matter what you send it to. The current will simply seek whichever plug has the lower resistance.

Stephan