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  #1  
Old 10-14-2002, 11:10 AM
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cuda66273 cuda66273 is offline
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Default Mission Ignition

Chapter one....Coils

Coil's are probably one of least understood items in the ignition system...let me try and explain the differences in a simplistic form here...

The coil builds voltage and when the signal is sent from the star wheel/magnetic pick-up in the distributor to the box the box then throws power at the coil which in turn shoots the spark to the correct terminal in the cap by way of the rotor and of course this sparks the plug. This we all know right?

Coils are designed to operate just like a camshaft...or with a certain operating range.

The windings inside the coil are increased or decreased to operate within an RPM range depending on the RPM demands of the engine.

A stock coil is designed to operate best at let's say between 400 and 4500 RPM whereas a Blaster 2 coil operates best between say 3000 and 7500. When demands are placed on this component that exceed the operating band, the efficiency decreases, as does the spark efficiency. The end result is a poor running engine once you get out of the power band.

So...your coil needs to be matched to your specific demands much the same way as a camshaft. Blaster or Accell coil on a stock engine will not be an improvement, rather a backwards step. If we take a Blaster 2 coil for example we find that it is very inefficient at low RPM, the multi spark box cloaks this by firing multiple sparks at the plug to make it operate efficiently…kind of a band aid or trade off…but a good one.

In running these different types of coils on our distributor machine we have found for most street/strip warmed up motors the Blaster 2 and Accell coils seem to have the best power band for what most of us do, so just as in proper cam selection there are variables to be considered when choosing the correct coil.

One more interesting note here….when we run anyone's distributor and coil up to 7500 we have never found one that actually works….the plugs become glow plugs like in a diesel and the combustion chamber becomes a self igniting atmosphere. We have not yet found a distributor company that will give us the specs on their ignition above 7500.

Chapter two....Multi spark systems

So now lets look at what happens at the extremes of the MS (multi spark) systems.

Without getting into the intricate circuitry of these performance boxes I'll try to clarify what they do and why.

I've overheard people proclaim that the MS (Multi-spark) boxes put out anywhere from 3 to 50 signals to the plug every time the pickup coil sends a signal.

The facts are....below 3000 RPM the MS units fire the plug 20 times, over 3000 they simply send one shot to the plug. When we run these boxes on our Buzz Box with a plug attached you can actually hear the tone of the spark change and it's not subtle, it's a definite change of pitch.



Chapter three: Cap/rotor Phasing:

This is another part of the ignition tune-up that is almost never addressed. So called Super Tune shops are aware of this inherent problem with Mopar distributors (and others) and it's one of the first things they check.

Simply this is getting the spark signal to the plug by aligning the rotor and cap contacts so the spark travels to the plug at the instant that the two components are aligned or phased.

The Mopar distributors almost never do this, the rotor is either not yet at the contact or it has long since past it's optimum point. What this does is cause the spark to have to jump or arch to the cap, this causes heat energy. If we go back to basic physics we know that "Energy can never be lost it only changes it's characteristics" so what we do here is convert electrical energy to heat energy and effectively reduce the power of the spark as RPM increases and compression in the cylinder increases causing a higher resistance for the plugs the spark efficiency is drastically reduced...result....poor performance...lost HP and tork.

The cause of this phasing problem is multiple, the biggest thing we find is the vacuum advance plate on a Mopar distributor is really a poor design allowing it to tip and wobble in the distributor housing....when you get your distributor back from us you'll find that plate welded solid and the advance curve is controlled by the weights and springs. Bad bushings, worn gears, poor factory tolerance, cheap caps and rotors can all contribute to or multiply the phasing problems.

We cure this with a special cap that has holes cut in it so we can actually see the rotor hitting the contacts, we calibrate it and weld it in the correct phase....problem solved.

It's very common to find a Mopar distributor with the phasing so far off that at around 5000 RPM and up the rotor will get confused and start arching to either the contact ahead or behind it's position....ever heard this "I have a high speed miss I just can't find".....we hear it everyday and just smile....

Of course the investment in a high dollar MSD or similar type distributor is a solution and after we run them up on our machine, calibrate them to your specific engine they are excellent, but....most of us here are using our cars as daily drivers and go blast off a few 1/4 passes on the weekend. This is why we work over the stock distributors and or the Mopar Performance distributors (which are better for more performance orientated cars) and make them work to spec or "Blueprint" them for a fraction of the cost.


Chapter four: The tune-up

So now we're building a recipe for a performance tune-up and through these discussions we've determined that:

1. Carb selection is done by cam duration, compression ratio, gearing, RPM and CID.

2. Ignition systems need to have the correct coil based on RPM and power range. A high RPM coil can be made to work well with the addition on a MS box to multiple fire the plug at low RPM and once it gets into the higher end of the RPM band it does the job well with a single spark pulse.

3. Advance curve is determined by the ability of the carb to read the manifold signal at idle, top of the RPM range, and compression ratio.

4. Phasing of the cap and rotor is critical to ultimate performance and just as important as new plugs and wires.

Tune-up tip......if your running a MS unit and hot coil do not attempt to use a cap with a carbon rotor contact, this is a point of massive resistance and will cause tremendous heat to build at high RPM and can actually melt your rotor or at minimum heat the plastic up enough to allow that cheap cheesy rivet in the rotor arm to release and the rotor fall apart. Get a good cap and rotor and carry a spare.

Although there are many other fine details that need to be looked at for each of the above, this is a simple list giving you a good general scope of the science of a performance tune-up.

For those of you out there trying to tune your 30 year old distributor that's been rebuilt in Mexico 4-5 times over it's life…. forget it, you'll never get it working right until we do our magic hocus pocus on it.

Please feel free to copy and distribute this information to fellow Moparians and Motorheads…but please include the signature line.

This is Cuda66273 for Mopar Mystery's…. soon available in paperback….well, maybe copy paper….

Questions? cuda66273@hotmail.com

This information is based solely on the Authors personal experiences and not to be assumed that the manufacturers of any products mentioned recommend them, always consult with the manufacturer or a qualified technician before making any modifications to your engines
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  #2  
Old 10-14-2002, 12:32 PM
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Hey Ed your fast!
I was just trying to find the button to push to email you and zap there's a sticky on it...LOL
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Old 10-14-2002, 06:08 PM
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They don't call me fast Eddie for nothing...
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  #4  
Old 10-15-2002, 03:35 PM
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I wish I had info like that years ago! Instead of trial an error for my own personal learning curve (mostly error)! Why did Mopar include so much darn vacum advance built in??? Who knows keep up the good work!

Bob
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  #5  
Old 10-15-2002, 06:25 PM
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Smile

Hi Don, I did not ask you in my last e-mail, are the mallory unilite distributors a good unit for a 440? Any experience with them? Thanks, Jeff. By the way I think the elevation at the track where I race is about 900ft. above. (Oceola, IN)
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  #6  
Old 10-17-2002, 05:36 PM
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Default Ignition phasing

Cuda, your article on ignition phasing brought back memories from the late 70s when i owed an AAR Cuda in high school. Then i had a dual point distributor from Accel in the 340 and Every time i'd bring it up to 5800 rpms it would break up like crazy. At the time i replaced anything i thought might be causing it but it continued but every once in awhile it would go away and i was able to shift the car at 6600 like i use to.Boy did i pull alot of hair out trying to figure it out. Beeman
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Old 10-17-2002, 11:08 PM
340king 340king is offline
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Thumbs up Clarifications

Thanks Cuda for posting this interesting series of articles. There are a few things that I would like to clarify.

First, the secondary voltage(spark) that leaves the coil is generated by the magnetic field collapsing when the primary voltage(battery) is removed from the the coil and not when it is applied. The purpose of the breaker points was to charge the coil when they were closed and break the connection when they were opened, hence the name breaker points. The spark is created when the voltage to the coil is cut.

Some other things that weren't covered in full detail were the other advantages of the MS boxes. One very good advantage is that they use capacitors to store voltage between cycles. This creates two advantages. First, the capacitors provide a full 12 volts at startup(the voltage doesn't drop as much when the starter is engaged). This helps reduce cranking. Secondly, the capacitors work like shock absorbers for the electical system and help keep the voltage to the coil more consistent, especially during high rpm usage. They actually help push the coil saturation at high rpm.

One final thing that comes up with Mopar ignition systems is the poor fit between the distributor drive and the distributor. Care should be taken to check the tolerance of this fit and modify the parts as necessary to reduce any free play. This can be due to two things. One is that the distributor drive can be larger than the end of the distributor and the shaft can rotate slightly when engaged. The second and more rare case is when the distributor drive tries to move up and down in the block due to camshaft vibrations or wear in the block bushing. Most people, experienced or not, fail to check this tolerance. Both of these can cause the timing to jump around a couple of degrees.
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  #8  
Old 10-18-2002, 01:20 AM
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340King: Excellent addition to the post! Thanks.

I always try and keep my tech info to the simplist terms and try and explain it in laymans terms. Some complex details are left out to keep the post as short as possible and not confuse the end result which is a basic understanding of how all things work together to achieve maximum performance.

Knowledgable folks like yourself adding in short details on specific engineering facts are what this board is all about..Information...as much or as little as one can absorb.
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  #9  
Old 10-19-2002, 09:14 PM
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340King, arent the capacitors used to boost primary coil voltage to 300V or so?

When a coil is used to step up voltage, it has to work with 12 volts. 12 in, 15K out. When you are stepping up 12 volts to 15K, it takes a little time and without the proper amount of time, itll never reach 15K (or more). When you have a motor running at 6500 RPM, or running at idle with as many sparks as the transistor can supply in 20 degrees crank rotation, that is alot of sparks to generate, all with the same 12 volts. Enter a capacitor.
With the ability to store 480V in a millisecond and discharge that into a coil, it makes the coils work alot easier because now the coil is not stepping up 12 volts, it is stepping up 480V. If you look at a graph of a coils stored energy potential, youll see it rise with time (rise time) if you discharge the voltage before max saturation, you dont get max voltage. Dual point distributors cheated by holding the breakers open longer, allowing the coil to disharge a longer spark before the closed points start the rise cycle again.

I personally witnessed 7 timing marks at idle with an MSD6AL and a Craftsman powered timing light. I dont know if the timing light was a factor in that but 7 sparks in 20 degrees@ 800RPM is alot to ask of a coil without CD, and that is good to 3000, then the single fat spark is introduced.
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Old 10-19-2002, 10:45 PM
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cuda Ive rephased and recurved distributors for many years also and have come up with a simple method w/o sophisticated equipment,the fanciest being a dialback timing light,1st I solder the vacuum advance solid,2nd at warm idle I keep advancing the timing while monitoring a vaccum gauge,when peak vac is reached I back off 1" for lightweight cars(under 3000lbs)and backoff an addt"l .5" for every addt"l 500 lbs,this will be ideal idle timing as read at the timing mark,for instance my 10.5:1 360 liked an initial 18*,be sure that it doesnt crank hard when hot,if so keep backing off until it doesnt then go an addt"l 2*,now I have already acquired a total timing # from many dragstrip runs,it went fastest at 34* total timing,it went just as fast all the way up to 40* before it slowed but didnt go any faster so I want 34*,why? because detonation will be much more avoidable,so now I have 18* initial as but dist gives me 48* total when the initial is so high,Ive seen way over 50* many times so now i put the dist in a vise and with a degree wheel I want to limit the mech advance to (34*-18*=16* at the crank divide by 2 for camshaft * and you get a mere 8*)so with the degree wheel around the dist shaft and a rotor with an extended tip (just JB a piece of hanger to it)I can advance the rotor to 8* and scribe the end of the mech weight slot so Ill know where to drill a hole so it will become a new stop,use a .090 drill bit and find some leftover u-joint needle bearings,they usually measure .092-.094 and drive it home plus their exceptionally strong.Now for the phasing.cut away a cap so you can see at least 2 in cap wire contacts,fire the motor up in a very dark enviroment and aim your dialback timing light to the same contact that your light is hooked up to.I always shoot for perfect alignment at the middle of the curve(my curve is 16* long so add half(8*) to my initial)=26* for perfect alignment,now Ill remove the reluctor(pry up gently with 2 screwdrivers) and move it a slight amount then run it again,if its loose without the pin you can stake the shaft gently,when you get it where you want it simply stake it in 8 different equal spaces and use locktight,disregard the pin.Just a note Ive had several dist where the reluctor was so sloppy this wasnt possible but Ive found its the reluctor i.d. that varies not the shaft so you may have to acquire another($4).I know this sounds lenghty but I can do 1 in about 30 min total and it cost very little and it ALWAYS makes a huge differance especially if the engine is extremely modified(hdrs,cam,int,carb etc)usually youll find 15-30hp!!!but the real benefit is the driveabilty is always near spot on,be prepared to rejet your carb,so check your plugs after doing it,The real benefit is its now custom curved to YOUR engine,not some magazines reccomendation. Better yet is an Accel dist that has a completely adjustable mech adv but be prepped to hand over bigger $,hope this helps .............PRO........
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  #11  
Old 10-20-2002, 08:54 AM
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Your doing pretty much exactly what we do, but most members here and our customers just don't have the expertise and tools to accomplish this on their own.

Before we curve a distributor we try and get all the information you mentioned and also the carb info. This allows us to get the distributor real close and end up with a 98% success rate.

For under $100, it's way easier to send them to us than to buy the tools and try and figure it all out.

Obviously your not going to be a very good customer...but that's why your handle says "PRO"...cause you are!
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Old 10-21-2002, 07:31 PM
340king 340king is offline
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Wink Electronics

It has beena while since I spent much time thinking about electronics, or lectroneeks as ole DW would put it. From what I remember, capacitors work like storage reservoirs. The thing is that they don't like to change voltage much. The typical use is to have them regulate voltage in areas where changes in voltage aren't good. Also from what I remember, capacitors can't change the input voltage by themselves, a coil(or other voltage amplifier) is required for that. I don't know if MSD uses a transitorized voltage amplifier in their boxes or not. One thing to consider is that the insulation around your primary wires is probably not good enough to support 300 volts. Something less than 200 volts is probably more like it. Remember it is different for DC than it is for AC. After that they might leak (spark) voltage to objects they come into contact with. So, I don't think that MSD jumps the voltage up that much over the 12 volt range. There is a little thing I remember about current lagging voltage in discharging coils or was it the other way around? At any rate, the capacitors act like voltage reservoirs and can be setup to charge rather quickly. This ensures a quality supply to the coil.

I think it would be good to post that question to MSD for their response. I assume they have a website to send things like that to.
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Old 10-27-2002, 08:19 PM
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So how fast do you wantt the advance to come in? As fast a s possible? What is done to the MP distributors? just lighter springs, and/or heavier weights? I would imagine my 383 powered truck would tend to want a slightly less agressive advance than the MP distributor has. I will use the orginal 400 stock distributor, instead of the MP one that is in the 383. The Engines book (I believe) said all mech advance should be in by 2000-2500? How do you tune the vac advance, doesn't the nipple screw just adjust the spring tension/speed of advance, but you still need to weld/grind to adjust the total vac advance?
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Old 10-28-2002, 09:49 AM
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So how fast do you wantt the advance to come in?
This depends on your cam, intake maifold, gear ratio, tire size and convertor stall speed.

What is done to the MP distributors? just lighter springs, and/or heavier weights?
They have a different rate of advance and can be adjusted for max curve through the vacuum advance module. They're not bad but need fine tuning to get then right for your specific application and this is really best done on a distributor machine.

The Engines book (I believe) said all mech advance should be in by 2000-2500?
That's a big spread.....and needs to be calculated precisley to each engine based on (see question 1)

Distributor curving although not extremely difficult requires a good distributor machine and years of experience in knowing where to set everything for max performance and drivability.
We have a few tricks up our sleeve from the years of experience part of it to ensure both.

We have run up some distributors that just don't need anything done to them, although rare, sometimes the application and the distributor just match up right.

It would take me hours to sit here and type out all the info we have as a base line for different applications and none of it would help unless you have a machine to spin it up and make the correct adjustments.

When we do a distributor we also dial it to the Box...we have seen MSD boxes vary as much as 3-5* in timing so it's important that we have your box to set the distributor up correctly. If you change the box from say an Orange POS to a MSD or HI-6 or vise versa you could actually be off as much as 8-10 degrees either way at 5500 RPM...this is a serious event and could cause catastophic failure...Poof..

I can say this...if we do your distributor you'll see it in your time slip and quite possibly on the seat dyno.
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  #15  
Old 10-31-2002, 12:51 AM
340king 340king is offline
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Default The Great Piston Hammer

Being so close to Halloween reminds me of my favorite Charlie Brown and the Great Pumpkin. It has nothing to do with distributor curving.

From what I can remember from some learned fellows that have logged many more hours on the dyno than I have ever dreamt, full advance before 3,000 can bring out the Great Piston Hammer(detonation). I can't remember where I read it. It was in print, so it must be right! Where your curve is depends a bunch on what you drive, how you drive, what gas you run, etc.

I have a couple of locked distributors that I run on circle track stuff. 36° when cranking, at idle and wailing at 7,000+ rpm. The old adage, simpler is better comes to play there. If you don't run any weights or springs, they can't get messed up. The thing here is that you have to be careful not to stomp on it at low rpm with a load on the engine. Otherwise its hammer time
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Old 11-05-2002, 06:47 PM
senor RR senor RR is offline
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Question Cap/Rotor phasing

Quote:
Originally posted by PRO
cuda Ive rephased and recurved distributors for many years also and have come up with a simple method w/o sophisticated equipment,the fanciest being a dialback timing light,1st I solder the vacuum advance solid,2nd at warm idle I keep advancing the timing while monitoring a vaccum gauge,when peak vac is reached I back off 1" for lightweight cars(under 3000lbs)and backoff an addt"l .5" for every addt"l 500 lbs,this will be ideal idle timing as read at the timing mark,for instance my 10.5:1 360 liked an initial 18*,be sure that it doesnt crank hard when hot,if so keep backing off until it doesnt then go an addt"l 2*,now I have already acquired a total timing # from many dragstrip runs,it went fastest at 34* total timing,it went just as fast all the way up to 40* before it slowed but didnt go any faster so I want 34*,why? because detonation will be much more avoidable,so now I have 18* initial as but dist gives me 48* total when the initial is so high,Ive seen way over 50* many times so now i put the dist in a vise and with a degree wheel I want to limit the mech advance to (34*-18*=16* at the crank divide by 2 for camshaft * and you get a mere 8*)so with the degree wheel around the dist shaft and a rotor with an extended tip (just JB a piece of hanger to it)I can advance the rotor to 8* and scribe the end of the mech weight slot so Ill know where to drill a hole so it will become a new stop,use a .090 drill bit and find some leftover u-joint needle bearings,they usually measure .092-.094 and drive it home plus their exceptionally strong.Now for the phasing.cut away a cap so you can see at least 2 in cap wire contacts,fire the motor up in a very dark enviroment and aim your dialback timing light to the same contact that your light is hooked up to.I always shoot for perfect alignment at the middle of the curve(my curve is 16* long so add half(8*) to my initial)=26* for perfect alignment,now Ill remove the reluctor(pry up gently with 2 screwdrivers) and move it a slight amount then run it again,if its loose without the pin you can stake the shaft gently,when you get it where you want it simply stake it in 8 different equal spaces and use locktight,disregard the pin.Just a note Ive had several dist where the reluctor was so sloppy this wasnt possible but Ive found its the reluctor i.d. that varies not the shaft so you may have to acquire another($4).I know this sounds lenghty but I can do 1 in about 30 min total and it cost very little and it ALWAYS makes a huge differance especially if the engine is extremely modified(hdrs,cam,int,carb etc)usually youll find 15-30hp!!!but the real benefit is the driveabilty is always near spot on,be prepared to rejet your carb,so check your plugs after doing it,The real benefit is its now custom curved to YOUR engine,not some magazines reccomendation. Better yet is an Accel dist that has a completely adjustable mech adv but be prepped to hand over bigger $,hope this helps .............PRO........
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Old 11-09-2002, 01:57 AM
Brian Mills Brian Mills is offline
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Hi Don. You've sparked my interest, (no pun intended). I see you racers have the ignition system well in hand, the info from you and PRO is flooring me, secrets like this I've never heard.

In all fairness, I looked in the Engines book and I'll give a quick overview since people are mentioning it, and it is quite obvious that this thread is way beyond the bolt on kit.

A typical factory advance system is 3 part:

1-Initial, which is where you set timing at idle with a timing light.

2-Primary, done with weights and springs, comes on between 500 to 900 RPM goes to 2500 approx. it is a fairly steep advance.

3-Secondary, done with the weights and springs, starts about 2500 RPM, not nearly as steep a curve as Primary, goes to 5000 RPM approx.

* Primary and Secondary added together are known as centrifugal or mechanical advance.

Vacumm is an add on or supplemental to increase economy during engine operating times of high vacumm, coasting down hills etc. NOT USED BY RACERS. Takes timing to 54 degrees advance during times of high engine RPM while not under heavy load.


The Mopar Performance curve starts at 900-1200 RPM, so your race engine can have a higher idle and still maintain initial, where you set it timing.

Primary advance starts at 1200 RPM approx., and climbs sharply till all in at 2000 RPM approx.

Secondary advance is deleted.

* Centrifugal or mechanical advance is now all done in the primary step.

Vacumm advance is the same as factory. The factory unit has 16 degrees of advance that can be decreased to a lower number, not slowed, by the allen screw adjuster.

So that is the 9th edition overview. I know I had to read it again to see the difference between this and what you and PRO are actually acomplishing.
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Old 11-13-2002, 03:54 AM
John at J&S John at J&S is offline
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There are two basic types of ignition systems. Inductive discharge, and capacitive discharge.

In an inductive discharge system, the coil does two things. It stores energy in the form of a magnetic field, and it acts as a step up transformer.

An inductive discharge system is what comes stock on most vehicles. The coil has +12v on the positive terminal, and the negative terminal is momentarily shorted to ground by either a set of points, or a transistor. During the time that the points are closed (or the transistor is on), current starts flowing in the coil, building up a magnetic field in the coil primary.

When the points open (or the transistor turns off), the magnetic field collapses, generating a high voltage in the secondary, causing the spark.

Point systems needed a ballast resistor to prevent burn out at low RPM. They were limited to about 4 amps of current. Modern systems adjust the dwell angle (on time) with RPM, and can adjust the dwell with RPM to maintain 5.5 amps (GM HEI) to 6.5 amps (Ford TFI).

If you double the coil current, the stored energy quadruples. Most transistorized ignitions have a built in current limiter, to prevent burnout during slow cranking. It also allows for sloppier dwell control circuits.

Most coils take about 3 milliseconds to reach 6 or 7 amps of current. They are not like a resistor. Instead, the current ramps up linearly, like a sawtooth. This is where inductive systems are limited.

At 7000 RPM on an 8 cylinder engine, there is only 2 milliseconds between firing events. You can see that the coil doesn't have the time to ramp up to the desired current level.

One thing you can do is to run a higher voltage battery. This has the effect of steepening the coil current ramp, so it gets to the desired level sooner. That's the principle used in the Kenne-Bell Boost A Spark, and a similar product by B&M. They raise the coil positive voltage to about 20v. These systems can help only if the built in current limiter has not kicked in, such as at high RPM.

****
Capacitive discharge ignitions operate on a different principle. A capacitor is used as a storage device, and the coil is used only as a step up transformer.

The negative terminal of the coil is typically grounded. On the MSD6, and the Crane Hi-6, the Black coil- wire is grounded inside the box. The coil positive is connected to the box with an Orange wire. Inside the box, it's connected to one end of the storage capacitor.

These systems use what is called a dc to dc converter. They take 12 volts dc, turn it into a square wave, run it through a tranformer to get 400-500 volts ac, then filter it to get 400-500 vdc, which is then used to charge up the storage capacitor. All that takes about a millisecond.

When it comes time to make the spark, the high voltage side of the capacitor is shorted out with an electronic switch. This has the effect of placing -500 volts on the coil positive, which is then stepped up by the turns ratio in the coil, producing the spark.

The voltage rises very quickly, blasting through contaminates. Inductive systems have a slower rise time, and can misfire easier with fouled plugs

Compared to an inductive discharge system though, the spark is relatively short. At low RPM, these systems use a series of multiple sparks. Above 3000 RPM, the system makes just one spark.
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Old 11-15-2002, 08:35 PM
340king 340king is offline
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Thanks for the clarification on the capacitor discharge systems. I have just bolted the stuff on and had it work flawlessly and never wondered how they worked.
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  #20  
Old 11-23-2002, 10:17 PM
raymond raymond is offline
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Default A better cap and rotor

Hey Cuda or others , has anyone got any thoughts on a better cap and rotor than the MP one? I have several MP ones and they all seem to have a huge air gap between the rotor tip and the terminals in the cap. I'm talking probably over .100" and that seems too much to me. The only other cap and rotor package I have seen advertised is the Accell one. Has anyone had any experience with this piece?
I'm in OZ and this stuff is not exactly thick on the ground, any help would be much appreciated.
Thanks
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  #21  
Old 11-24-2002, 01:38 PM
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cuda66273 cuda66273 is offline
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I got your email on this and I had to check a few distributors to see what the air gap really was...as this not ajustable it just never occured to me to check it before...seems anywhere from .90-.100 is normal.

I can tell you that the Accell cap and rotor seem to be the best for low resistance and the stock and cheapo caps are pure junk....

If you get an Ohm meter and read the resistance from the contact inside the cap to the plug wire contact on the top you'll see what I mean.

Resistance generates heat, heat is our sworn enemy and it will kill our ignition system. Take a look at a rotor, see those little plastic tabs that hold the rotor contact in place....I've seen those melted. Look at the way that the rotor contact is attached to the plastic, that little rivet is twisted into the plastic, gets hot the plastic expands and the rivet gets loose or falls out. The heat generated by the high resistance in the aluminum contacts in the cap can and will melt them down...I'm sure you've seen this happen.

Every ignition manufacturer at PRI is on my hit list for next week, I'll be giving them all the 3rd degree and search out the best product for high output ignition systems.
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  #22  
Old 11-26-2002, 03:44 PM
Brian Mills Brian Mills is offline
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RIGHT ON DON! Our man on the scene! I've been happy with MP, but when I don't know any better, I should be. You are going to become a distributer for one or more of these ignition vendors I hope. Sure would be nice to deal with an informed person when I shop for better pieces.

On a side note. Have you heard that Daimler is looking at encouraging their dealers to open a Mopar speed shop in all their dealerships.
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  #23  
Old 11-27-2002, 01:01 PM
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cuda66273 cuda66273 is offline
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Ya I heard about this promo plan from the Great and Fearless German Leaders.......I believe the directive read......

Acktune all Dealashipz:

ve must sellz more chineze patz....za is buyink za hell outta our mercedez and ve need to sellz more of zar junk zo za can payun for zem.

Offer free chop zuey vith ezery orda of MP Chineze patz.

Ve vill send you a free slize of BBQ poke witz every orda.

zell zell zell...un rememba...nine on za varanteez...takz the marks an runz...





You didn't know I was bi-lingual did ya....
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  #24  
Old 12-04-2002, 06:49 PM
mopower440 mopower440 is offline
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about reluctor phasing, i am using the stock electronic distributor that came in the 1975 new yorker i got my 440 from, i drilled a hole inthe distributor cap to check the phasing, it was just a hair off, the rotor was pinting to the side of the #1 terminal instaead of dead on it, i dont mean to the edge of it, just not perfectly dead on, BUT i do not use the vacuum advance, so should i buy one of those cnc machined reluctors to try to get it dead on, or is it a waste of time since i DONT use the vacuum advance and since it is still pointing to the right terminal, just not perfectly dead on it?
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  #25  
Old 12-05-2002, 10:38 AM
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Yes...it needs to be right on the money
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  #26  
Old 12-05-2002, 06:00 PM
mopower440 mopower440 is offline
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well, let me tell you what else i did, the old cap i drilled the hole in had the little tab on the bottom broke off, the one that holds the cap from moving, well,i fired the motor up and pointed the timing lite in and turned the cap a hair to make the rotor point dead on the terminal, and the idle did not change at all! i dont mean that i turned the whole distributor, JUST the cap, to make the phasing right on the money, since it didnt change anything, should i still get the reluctor?
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  #27  
Old 12-06-2002, 03:11 AM
fat bastard fat bastard is offline
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The cap is the phasing part of this process, timing is changed with the relationship of the mag. pickup and reluctor. Sounds like you are ok, but I'd invest in a decent cap to prevent any movement. Actually if I were you I'd also invest in some basic tuneup tools such as timing light/tach/vacuum gauge/manuals. Working on a car thru the computor is one thing, but putting your hands on it is a completely different ball game. Try it, you'll like it.
FB
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  #28  
Old 12-06-2002, 08:32 AM
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I think I have taught you guy's too well....you've learned all my secrets....LOL

Keep you fingers out of the fan.....
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  #29  
Old 12-06-2002, 12:16 PM
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ehostler ehostler is offline
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Quote:
Originally posted by cuda66273
Keep you fingers out of the fan.....
But the fan makes such a neat reverbating twang sound, when you put your fingers in there. Besides, it doesn't hurt (much) when you put your fingers in there. It only throbs for a while afterwards.
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  #30  
Old 12-07-2002, 01:22 AM
Brian Mills Brian Mills is offline
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No Don. I was not aware of your second language. LOL.

On a serious note. Do you know anything about the Hall Effect distributers used on fuelie engines?

Any improvements for these?
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