Ignition planning/understanding

[standup303]

Hey guys, I am starting to plan out my ignition and wiring setup for my 440 swap in my 74 Dart Swinger. I labeled the factory harness as best I could when taking it out but quite honestly don’t know why the hell half the little modules are. I have been going through wiring diagrams trying to identify them to see how I can clean them up.

For instance I read with a MSD AL6 I could remove the ballast resistor?

Would the AL6 also incorporate an ignition resistor?

I can’t remember for sure but I feel like I did not have a starter solenoid and the positive wire came straight off the starter relay?

The alternator regulator, is this just a voltage regulator?

Control unit, is this the 4” x 5” box bolted to the top of the driver fender well?

Any help is appreciated, thank you.

 

[halifaxhops]

Post pics.

 

[Brooks James]

No ballast needed with MSD6AL.
It draws 1 amp per 1000 rpm

 

[Kendog 170]

Starter solenoid is on the starter.
The alternator regulator, is this just a voltage regulator? Yes
Control unit, is this the 4” x 5” box bolted to the top of the driver fender well? Yes.This is what your replacing with your MSD .

 

[Bewy]

Unless this is some big HP engine, switching to MSD 6X will just lighten your wallet....& nothing else.

 

[RustyRatRod]

Starter solenoid is on the starter.
The alternator regulator, is this just a voltage regulator? Yes
Control unit, is this the 4” x 5” box bolted to the top of the driver fender well? Yes.This is what your replacing with your MSD .

Umm....what? The starter RELAY is on the firewall.

 

[67Dart273]

You need a (free) factory service manual SEND ME A PM and I will get you one

The diagram you posted is 3rd party and leaves out a whole bunch of "stuff." It is however, sometimes easier to follow

MSD NEVER needs a ballast and works entirely different than the stock igntiion

Stock, old school breaker points, the later Mopar electronic, the aftermarket Pertronix, The GM HEI which can be adapted (the module) and the cheap China "ready to run" distributors, whether points or electronic, are sometimes called "Kettering" or "switched." The work by switching the ground leg of the igntion coil, which is usually fed through a ballast

MSD is a type of CAPACITOR DISCHARGE and like it and other CD ignitions, they NEVER use a ballast and work on a COMPLETELY different principle than the above systems. CD type systems work sorta like a camera electronic flash---a high voltage power supply charges up a fairly large value capacitor (condenser) and when triggered, discharges through the coil

Whether you want/ need one or not depends on personal preference, and HP rating. Many MANY high performance engines run just fine with something else.

WITHOUT PHOTOS just a guess is "the box" you are talking about is the VR or voltage regulator. IT has a sort of triangular 2 terminal connector, blue and green wires

The ignition box on those (factory) is normally mounted to the fender apron. Right side for stock stant six and left side for V8

 

[Kendog 170]

Umm....what? The starter RELAY is on the firewall.

He asked about starter solenoid not relay. Starter relay is on fender well not firewall.

 

[Bewy]

The MSD 6X instructions say that the bal res can be left in place & operational.
'Bal res may be removed on MSD 6,7,8 series, as they do not affect performance'.

 

[RustyRatRod]

He asked about starter solenoid not relay. Starter relay is on fender well not firewall.

I gotchya. I had head up *** syndrome. I'm not sure I ever really get over it.

 

[Bewy]

Have you tried vaseline.....

 

[RustyRatRod]

Have you tried vaseline.....

You be quiet and go fix your toilet. LOL

 

[MadScientistMat]

The first step in planning is to set the goals for the engine. Some questions to narrow things down:

1. What RPM range will it be running?
2. Naturally aspirated or forced induction? If forced induction, how much boost / nitrous? More cylinder pressure can require a hotter spark.
3. What sort of fuel? If this is on alcohol, again, that will need more spark.
4. Carb or EFI? While this doesn't change how much spark you need, EFI may have built in timing control features.
5. More of a street car or a race car?

Some of the biggest considerations for an ignition system will be:

1. Is it delivering spark with the correct timing? For a street car, you will also want vacuum advance, not quite as important on a race car.
2. Can it deliver enough spark energy at your peak RPM?
3. How well will it hold up?
4. If it fails, is it important to be able to find replacement parts at your local parts store, or can you wait for something to be delivered?

 

[Bewy]

^^^ Excellent post.

 

[AJ/FormS]

for the street;
IMO
Multi strikes on the street are for cams bigger than 250@.050 (the biggest I have run which did NOT need a MS, nor a CDI), or for low-cylinder-pressure, open-chambered slugs, or for guys who have trouble tuning their stuff.
IMO
If the first spark has lots of amperage, and comes at the right time, that will solve your problems...... which means that your Vcan has to be functional and tuned.
You can get additional power from your factory-type coil, by feeding it full battery power (usually 13.5 or better when running), at WOT, thru a relay, instead of the meager 8.5 volts it might get from the ballast. Don't run it like this continuously, as, over time, it may overheat, may explode, may make a stinking mess, and then leave you walking. But for the five seconds it takes to get up to 60/65 mph, it will be fine.
But I can tell you, in most cases, it will make absolutely no difference on the street at WOT.

 

[Bewy]

You might want to read the technical discussion on this website, www.worldphaco.net.

He compares CD ign [ MSD & other 6 boxes ] with inductive ign. The GM HEI inductive ign pretty much levelled the playing field & is hard to beat except for an all out competition engine.
Think about why GM style HEI dists are now available for non-GM engines.......