MSD wiring advice (connectors) - Page 2

blau911 · 01-03-2005, 11:36 PM

Guys,
I just bought a MSD and Blaster coil for my 67 911S. My current CD box is a blue Permatune with 6 PIN adaptor and a Bosch blue coil.
Can I assume that the wiring for the Permatune set-up is the same as the early Bosch CDI 6 pin unit , or is the wiring completely different? If it is, can I assume that all I have to do is follow the above directions posted for switching out the Bosch unit?
Somehow, with my luck, it will be completely different and I will be monkeying with this for the next 6 months. Any advice would be appreciated....

RoninLB · 01-04-2005, 12:27 AM

Quote:

Originally posted by blau911

Any advice would be appreciated....

my install was a ground-up install. I saved stock harness then used wire connector blocks, not spade connectors. It wasn't the quickest install and it's a bit overkill, but it's as bullet proof as possible.

I don't recommend my install unless you Really want to do it. It's brainless but time consuming.

1st pic without Pertronix elec block and pre completion install.

2nd pic of Pertronix wire block.

blau911 · 01-04-2005, 02:57 AM

Just looked at the instructions and it looks pretty simple with the exception of two things:
1) The MSD instruction booklet states that I have the option of either using the white wire (connects to the points, electronic ignition amplifier output or to the yellow wire of a MSD Timing accessory); or
use a violet and green (magnetic pick-up connectore) which form the magnetic pickup connector. This connector plugs directly into an MSD distributor or crank trigger. The violet wire is positive and the green wire is negative.
Since I am using a Bosch distributor, can I assume that I will be using the white wire - not the violet and green wires?

2) Will my tachometer still work after I install the MSD unit? Since it already does using the Permatune unit, I would think it will.

Howard M · 01-04-2005, 03:33 AM

Keep your wire that now powers the tach attached between the distributor and the tach (routes through the engine compartment relay board wiring harness). Don't use the MSD tach wire. Tee into the current tach wire to trigger the MSD, per MSD instructions. Worked for me, and no tach adapter required.

Howard

blau911 · 01-04-2005, 04:03 AM

Howard,
So as I understand it, you are saying that I should use the white wire, not the violet and green wires, and I should splice this white wire to the existing connection between the tach and the distributor. Correct?

Howard M · 01-04-2005, 05:02 AM

Yes, I used the white wire (on my '76 911 with conventional points). I tee'd into the points output wire that then triggered both the tach and the MSD box.

blau911 · 01-04-2005, 07:57 AM

Ronin,
I originally saw that thread. You will note that it includes a link to this thread which I found more helpful since this thread discusses MSD application for existing CDI boxes with 6 pins.
On that note, I went down to the garage a little while ago to think over the current wiring while I prepare to do the changeover to the new MSD. One of the wires actually connects to a bolt which holds the engine shroud onto the top of the engine case. Can I assume that this wire is being used as a ground? Also, I noticed that one of the wires is running to my fuel pump. Can I assume that this wire is being used as the lead which would otherwise run to my ignition? Lastly, there is currently a wire running to the base of my distributor. Can't understand that one at all???

The instructions seem simple though.

They state that there are 6 lines which need to be connected:
2 wires go to the battery
(heavy red = POS / heavy black = NEG

2 wires go to the coil
(orange = POS / Black = NEG)

1 wire goes to the tachometer
(this is the white wire which should connect to my distributor/tachometer wire already in place)

1 wire goes to the ignition (red wire)

What else is there to know?

addictionMS · addictionMS's Garage

IF you are running the stock 3.0 dist, you can buy the short green wire which plugs into the dist, it has a funky plug on it, SRP can sell you the other side of that plug so you have a slick install, it is a stock Porsche part, but I know SRP knows waht it is and sells them, about $5 if I remember correctly.

Jim

blau911 · 01-04-2005, 09:02 AM

Jim,
I have a 2.0 liter 67 911S engine and distributor, how does your post about the 3.0 dist info apply to me, if at all?

randywebb · 01-04-2005, 10:31 AM

a good point - Howard also gave advice based on a '76, not on your '67. If you search the threads, you'll find that sometime in the early-mid 1970's PAG apparently changed the tach triggering circuits. I think Warren (Early_S_Man) posted on what was changed. You'll also find a post from me that my 73.5 _did_ work fine to trigger the tach. My bet is that you'll need mods to have your tach work.

People want to be helpful, but often the advice is based on their car, which can be inapplicable to yours. It will help if everyone states how they know something. Others run shops, or used to, and have a much wider range of knowledge, or they do something else for a living but have made a study of an area, e.g. brakes. So anybody asking a question has to ferret out who said what in which context....

Good luck.

RoninLB · 01-04-2005, 11:50 AM

Quote:

Originally posted by blau911

What else is there to know?

2 things.
- how to wire in the tach.
- how to wire in the dizzy

then you can remove and store the 6 pin harness, run all new wires. I use 10ga AWG for the main hot to the starter lug and chassis ground foreward of the tranny and inner fender ground, etc etc. Silver solder all connectors.

fred cook · fred cook's Garage

Chris,

I put a 6A MSD box in my '80 911SC several months ago. I put connectors on the MSD wires and plugged them into the 6 pin master plug. Just use good quality connectors and it will work well. If you have the rear window defrost relay, relocate it to a horizontal position and the new box will have room to mount neatly on the stock aluminum bracket. The only extra wire that you will need to run is a main power wire. I went under the car and using a large ring connector attached it to the main power lead on the starter. Just to be on the safe side, I ran the wire thru a piece of heat shrink to add some extra insulation. I fused the main power wire with a 20 amp fuse for additional safety reasons. Doing the job this way makes for: 1) a neat installation, 2) Easy to do and 3) the stock Bosch unit can be replaced easily. I have had no problems with the unit that I installed in my car. The engine starts very easily and runs even better! I will say that a stock Bosch CDI that is in good condition will probably be just as good as the MSD unit and I would not have done the switch if the Bosch unit in my car had not failed.

This is a picture of the installation in my SC. Note the 6 pin plug supported by a tie wrap.

Here is another picture from a slightly different angle.

The stock cover will still fit over the new unit with just a little of the right end visible beyond the plastic.

Good Luck with your project!

Fred Cook
'80 911SC coupe

randywebb · 01-04-2005, 03:03 PM

"Silver solder all connectors."

- Why would you do that? There is no strength issue.

RoninLB · 01-04-2005, 03:07 PM

Quote:

Originally posted by randywebb
"Silver solder all connectors."

- Why would you do that? There is no strength issue.

ok.. it's really not necessary.

addictionMS · addictionMS's Garage

blau911 ,

sorry if I confused you, but the thread started with a question about MSD's and cstreit states "I have a 3.0L with a stock dizzy... Which MSD trigger do I use? (White, or Violet and green) and where do they connect?"

So I gave him some additional info he could use.

Jim

pope · pope's Garage

I ordered an MSD 6AL the other day but before doing so I did extensive research here and through books/manuals so that I would minimize my blunders when the time comes.

This is following some of the stuff that's been said in this thread and especially Joe's diagrams which I've gone through the process of 'enhancing'

.

My case is the 1970E with a Permatune CDI (exactly the same as the Bosch for the purposes of this exercise) and that little ballast that processes the tach signal before it goes to the tach, which Warren was so very fond of

.

Two diagrams follow. The first is the before situation so that you can have a reference point to compare to your initial setup. The second can easily be compared to the first and the changes you need to do to get there.

Of course it's all theory for now. I'm waiting for:
1 6420 MSD-6AL, High Performance w/Rev Control, 4-6-8 Cyl.
1 8213 Coil Bracket, Universal
1 8222 Blaster Coil, High Vibration

I will then post a follow up.

fred cook · fred cook's Garage

If you have an old/non functional Bosch CDI, you could pull the male side of the master plug out and solder the MSD wires to the connectors. Then you would literally be back to a "plug and play" installation. I would do the installation with male spade connectors first to make certain that everything worked properly.

pope · pope's Garage

Exactly! That's what the 'original CDI unit connector' box is in the diagrams.

pope · pope's Garage

Installed!

Contrary to what I believed, I need to stick the tach adapter in there too. Otherwise the tach doesn't work.
I'll post more details soon.

Formerly Steve Wilkinson · 05-14-2008, 05:08 AM

One warning for those of you using the green and violet wires to the stock green distributor signal wire, which is coaxial and has a plug on the outer end with two tiny spade terminals: This works just fine if you can find a female connector that fits it perfectly, I'm sure (somebody posted earlier that it's the same connector as the WUR), but I kludged up an installation that used two tiny female spade terminals on the ends of the MSD green and violet wires.

Not a good idea: Three years of perfect running after installation of my twin MSD/twin plug setup, the car suddenly refused to start. Cranked fine but no spark. I checked everything for days and days and was on the verge of sending the boxes back to MSD when I finally discovered that my two female spade terminals had finally shorted out, inside my semi-potted terminal unit.

So that installation needs either a purpose-built female terminal plug or a dead-reliable insulator of some sort firmly between the two spades.

Steve Weiner, by the way, tells me that he routinely replaces the stock green coax distributor signal wire every few years; they're prone to sudden failure. I replaced mine even though the old one was still functional, as a precaution, when I did the most recent trouble-shooting work on the system. $51 from Pelican, but you might want to consider doing it. It's apparently a classic 911 failure point.