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Posted by: RiqueMar Aug 11 2011, 06:21 PM

I'm in desperate need of help with this CDI wiring on my conversion. The wiring I pulled off the 77' is just in horrible condition, as you will see in the pictures below, and I wouldn't be surprised if the wires are colored wrong or spliced wrong.

I'm not sure where each of the leads go, and I can't seem to find anything on an assortment of diagrams.

Posted by: 904svo Aug 11 2011, 08:38 PM

Check out this article it's on 6pin and 3 pin cdi boxes.
http://forums.pelicanparts.com/porsche-911-technical-forum/203100-6-pin-sc-turbo-cdi-unit-repair-documentation.html

Posted by: 9146986 Aug 11 2011, 08:49 PM

I don't have any of my wiring diagrams here at home, but the red one should be switched power, one goes to the points/tach, and the other goes to the ignition transformer (which looks like a coil but isn't).

Posted by: Cap'n Krusty Aug 11 2011, 08:53 PM

I have a pretty nice original harness if you want it, exchange. PM me for a price.

The Cap'n

Posted by: RiqueMar Aug 12 2011, 08:30 AM

Thanks Perry, would you mind checking when you get a chance? It would be most appreciated as this is the last article of concern in my Engine bay wiring.





Thanks Cap, but I'm just about done with my converted one, and I'm taking this challenge personally, I wanna conquer this thing!

Posted by: SLITS Aug 12 2011, 02:02 PM

Four wire to a 3 pin CDI box. Look at the end of the box ... terminals are labeled "A", "B" & "C"

"A" = to Terminal 15 on transformer (not an effin' coil).

"B" = Switched power B+

"C" = Tach input & trigger wire from points

Last wire CDI case to ground (spade terminal)

Posted by: RiqueMar Aug 12 2011, 02:03 PM

Is this the part where you slap me in the back of the head and say, 'Don't make me have to tell you again, kid"

Thanks Ron!

Posted by: SLITS Aug 12 2011, 03:12 PM

I was thinking more of a kick and not in the back of the head.

The connector in your pic had a mate and probably is the tach wire / B+ if there are 2 wires. Long harness went to transformer / dizzy (other side of transformer goes to ground - Terminal 1). Lonely wire is the ground on the CDI case.

Posted by: RiqueMar Aug 15 2011, 09:35 AM

Ok, so I've started pulling everything out, and I'm sure I'll have to do some work on this portion of the harness, as you've seen, it's pretty rough. Just have a few more questions...

I have the Red wire going to the positive terminal on the battery, my only issue now is that I don't know which of the white wires is which, because I have a Permatune Box and the numbers/letters don't seem to be there

Was this the connector you where talking about, Ron (see first picture)?

Posted by: Cap'n Krusty Aug 15 2011, 09:44 AM

That's not a CD unit, it's a Permadoom. Use it and, sooner or later, you'll be walkin'.

The Cap'n

Posted by: GeorgeRud Aug 15 2011, 10:56 AM

Weren't the blue ones OK? I thought it was the later ones that had the problems (but I certainly could be wrong!). My Bosch CD is still humming along, but I hate to see what it costs to have one rebuilt these days.

Are more and more people switching over to the MSD or other ignition systems as the original ones are giving up?

Posted by: SLITS Aug 15 2011, 11:24 AM

Wiring on the "Permadoom" is the same. My 2.7L runs better with the "Permadoom" than it does with the Bosch. "Permadoom" was OE to Porsche when Bosch couldn't get their act together.



Cost to rebuild a Bosch unit is $225 & up. Supposedly, the "Permadoom" cannot be rebuilt as it is potted. Never took one apart to find out.

Posted by: RiqueMar Aug 15 2011, 12:12 PM

Awesome!

And what about that plug that I was talking about? Can I eliminate it and am I correct in the red going to the positive terminal?

Pelican sells a 'Permatune Coil' will I need one or can I stick with the original black unit?

I know, I know, I'm a bottomless pit of "how" and "why" questions

Posted by: SLITS Aug 15 2011, 12:38 PM

Use a stock "TRANSFORMER - it's not a coil.

Yes you can cut the plug off and wire in (not the plug that goes into the CD unit).

Posted by: RiqueMar Aug 15 2011, 12:58 PM

Yes, I meant the one below with the black overspray on it.

Posted by: SLITS Aug 15 2011, 01:43 PM

And that's the one I meant. You probably could find a mating plug if you looked though.

As a side note, I carry a spare CDI unit at all times.

Posted by: RiqueMar Sep 5 2011, 08:11 PM

Reference for anyone else who stumbles upon this, correct?

Posted by: SLITS Sep 6 2011, 07:05 AM

Si!