Distributor wire connections

[FIAFRED]

Could somebody tell me where to connect the two ditributor wires (the third is taped off from my engine builder) on my MSD ignition? I have a 351 W from Southern Automotive, and am using an MSD Blaster coil. This is the only thing keeping me from firing up my engine for the first time! Please help!!

FIA Fred

[Bob Putnam]

This is what we do:
http://www.erareplicas.com/427man/wiring/msd.htm

[FIAFRED]

Bob,

Thanks for your schematic. The problem that I am having is that I can locate all of the components that are on the diagram except for the MSD 6A. I have a Ford High Performance Distributor with two wires for connection a black/red and a black/purple. The third wire is cut. What in the world am I missing in the picture? Thanks for your help!!

Fred

[Jack21]

The distributor wiring conventions have 2 leads coming from the distributor. These are for the magnetic pickup coil. + is purple, or black & purple, - is orange, or black & orange. The third wire is a ground that was used in some OEM applications. If you have a good chassis ground, you don't need it.

The distributor leads from the MSD should be identified by color in the schematic as to +, & -. The distributor leads out of the distributor should be similarly identified.

The MSD documentation should describe the symptoms of reversing the polarity. If all else fails, hook it up and if it runs OK, leave it alone. If not, reverse the leads.

[Bob Putnam]

Let me get this straight. You've got a Ford Distributor, MSD coil, but no "spark box" - MSD or Ford - in the system?

[FIAFRED]

Bob,

You got it right!! Can you tell that I'm a pilgrim? No I do not have a spark box, and didn't have the good sense to know that I needed one!! I Do know where the steering wheel is, and I Do have tires on the car. Bob what spark box do you recommend? I'll try not to ask too many stupid questions in any one day. God knows, I wouldn't want evryone to know that even the mentally challenged can get a driver's license!!

Fred

[Bob Putnam]

Well, I'm sure you'll get other recommendations too, but we use MSD-6A boxes in all our cars, usually at the recommendation of the engine builders. I think that the 6AL model also has a rev limiter built in, which comes in handy when you loan the car to your teenage son (or miss a shift yourself.)

There are some issues with Smiths tachometers covered in this thread

[FIAFRED]

Bob,

Thanks for the suggestion on the MSD 6A, and the 6AL. That is the flavor of choice from most, and is what I am going to use. Do you have any idea about what the cost is for the 6A? Just a ball park would be great. By the way, thanks for going past my limited knowledge of engine protocol. OK, so you had a good chuckle on your end... I can handle that! "Poorboy" aka Don, on the club forum has probably had the biggest laughs on my earlier dumb questions. You guys are great to be so patient with "the blind". Hey, I'm not proud, just very, very excited!!

Fred

[Bob Putnam]

Summit Racing has the 6A at $132 and the 6AL at $173 - probably similar to numbers that the other mail order people have.

[Okiesnake]

Bob Putman’s advice is always on the mark and his diagrams are fantastic. However, I thought you might also benefit form hearing from a fellow Unique Owner, even if it is a little redundant. I have a Unique Kit with a 351W with a MSD 6AL box and a Ford Duraspark distributor. I purchased the MSD6AL and MSD coil through Unique.
First of all, don't hook up any of the kits wiring harness to the coil. The wiring harness assumes you are not installing a high output electronic ignition. All that you should have hooked up to the coil is the thinner black (-) wire from the MSD and the orange (+) wire from the MSD.
The Heavy Red (+) wire from the MSD to the battery side of the starter solenoid and the Heavy Black wire (-) from the MSD to a good frame ground.
The black/violet wire from the MSD is butt spliced into the green wire of the distributor and the black/green wire of the MSD is butt spliced into the violet wire of the distributor. The black wire on the distributor is not used.
The thin red wire from the MSD is attached to a switched 12 V source (i.e. the ignition key switch).
The white wire from the MSD is not used.
Take an extra piece of wire and put an electrical female spade connector at the one end and attach it to the male spade connector of the MSD (Tach Output connector - the little black round connection on the end of the MSD). The other end of this wire is attached to the tach (S) signal connector on the back of your tach gauge.
Your harness came with a fusible link. You need to install it where they instruct (at the battery side of the starter solenoid).
Feel free to ask for help. I’ll be glad to e-mail or post any detail pics of my car if you like. Sometimes a picture really is worth a thousand words.
Good luck.
Okiesnake

[FIAFRED]

Okiesnake,

Thanks for the advice. I am happy to say that I hooked up my spark box exactly as you described, yesterday, and my FIA is running like a teenager on steroids. Life is good!!!

[Okiesnake]

Good for you!
You always remember your first time (starting the engine).

[patrija]

Awakening an old thread with an add-on question.

For a project, I am rewiring/rerouting some the ignition wiring on my Cobra. My Cobra has an MSD 6A ignition control, an MSD Blaster 2 coil, and a Duraspark distributor. The MSD 6A is mounted on top of the passenger foot box. The coil is mounted to the fiberglass on the driver wheel well.

I am focusing on two wirings connections: (1) the MSD 6A to Coil, and (2) MSD 6A to distributor. Both of these connections previously ran in in front of the engine by the expansion tank and the heat melted the tubing.

I've already rewired and rerouted the MSD 6A to coil connection. It now runs along the firewall and down the body lip of the hood to the coil. Seems to work great.

Here's my question:

I've heard of problems running the "MSD 6A to coil" and "MSD to distributor" connections close to each other. Believe it or not? And why? How close is too close? I'm considering running this tubing back to the firewall and then down the valley on the driver side valve cover to the distributor.

Also, a random electrical question to settle a local debate. Is there a problem splicing a heavier gauge wire into a lighter gauge? For example if the MSD to coil wire was originally 18ga and it was cut and respliced to a 14ga wire, such that the wire coming out of the MSD 6A remained 18ga with a splice to a new 14ga running to the coil. I got a six pack of beer at stake on on this one.

Thanks!
Jason

[Dave Samson]

The thinner the wire , the lower the current carrying capacity of it.
I'll be expecting that can of beer by air-mail before Xmas thanks.
Cheers,Dave

[patrija]

TTT.

Primary question is concern about running the distrubtor and coil wires next too each other?

Thanks
Jason

[FIAFRED]

Jason,

Sorry for the delay in answering your questions. My MSD 6A is also mounted under the passenger footwell. I drilled a hole in the firewall above the footwell at mid dash level and ran my tach, distributor, and coil wires through this opening. After leaving the firewall, I ran my distributor leads between the intake manifold and valve cover directly to the distributor. I sleeved the two distributor leads into the insulation sleeving that is available through JC Whitney, which comes in black, red, or blue colors. It is suppoosed to have thermal quality protection to 1200 degrees. I also mounted my blaster coil on the engine side wall on the passengers side. I shoved the coil leads into the same wire loom which feeds the alternator from the Unique harness. The wire loom lead on Unique's harness that used to run to the coil and distributor is no longer used except for the tach wire which goes to the MSD 6A now, and the wire which goes to the ignition switch. I pulled out these two wires from the loom at the fire wall and then ran each of them to their respective connections(tach on MSD 6A and Igniton switch). I have had no problems whatsoever with this configuration and it makes for a very neat layout in the engine compartment. Running the two coil wires from the MSD 6A directly to the coil has been fine. As have the sleeved distributor wires directly to the distributor, and laying across the intake manifold, next to the valve cover. Did this answer either of your questions? If I need to clarify any of this, just send me a note.

Fred

[patrija]

Perfect. Thanks!

[Dave Samson]

Jason,
You may also like to consider installing a suitable capacitor between your power source and the 6A for the sake of additional safety and in some cases, it is a necessity. In my case, I installed it for additional safety and to my surprise, the engine actually fires up faster and seems to idle smoother when cold.

If you need additional information on a suitable capacitor just ask.

Dave

[FIAFRED]

David,

While I have heard of having to install a capacitor, I'm not sure of what critia dictates the need. My 351W high performance engine cold starts instantly, idles fine, and runs like gang-busters. Can you elaborate?

FIAFRED

[Dave Samson]

Hi Fred,
The following is taken from another thread, I hope that the author doesn't mind.....

Being in Australia means we either pay 3 x the price that you pay for spare parts or we find an equivalent. I installed a generic 25V, 33,000 mF cap.

This is what he wrote:

Adding a Capacitor:
Here's the part you may have heard of, but never paid much attention to. Adding a capacitor when installing an MSD offers several advantages and is very benificial to a long lasting ignition. MSD calls it a "Noise Filter," but it is simply just a cap. Typically, these are used to help filter out any radiated noise from the ignition to your electrical system which can cause some radiated noise through your stereo. For most of us this won't be a problem. The important thing is that this cap also filters the power going to the MSD. This will prevent power surges and spikes from damaging the MSD. Things like jump-starting your car are very tough on sensitive parts, but using a cap will provide the protection you need.

At this point, you have the option of either ordering the MSD part (PN 8830), which is what I recommend, or going to your local electronics part store and picking one up. If you do the latter, you will need one of at least 25,000 microferrad and 16 volts. Anything bigger will be fine, but any larger than 50,000 microferrads will simply be overkill. Just make sure that it's at least 16 volts and not just a 12 volt cap.

To install the cap, simply run the power lead for the MSD to the positive terminal of the cap. Then run a wire from this same terminal on the cap over to the battery. At this point you have two options: You can either run the negitive lead from the MSD much the same way - to the cap and then to ground, or you can simply ground the MSD and then ground the cap - independently. (Both methods are shown below) Either way will work just as well, just go with whatever install method you think will fit your install best.

Understand that adding the cap may be the one thing that makes the differance between an ignition that lasts the life of the car -vs- one that only lasts to the end of the year. After having installed around a hundred of these Ignitions, I can assure you it really does make all the difference. The only two I've ever seen go bad, didn't have a cap installed.

Something to think about....

Cheers, Dave