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Eliminating ballast resistor... What coil do I need?

Posted By: Dusted_Ya

Eliminating ballast resistor... What coil do I need? - 05/11/09 10:46 PM

I'm replacing my old "F"d up electonic system with a petronics plug and play distributor system and would like to eliminate the ballast resistor as well. I was told that the old coils would fry if you ran them too long on 12 volts. I can't seem to get a straight answer out of anyone else as to which brand and model of stock appearing coil I need for this. One person said I need a breakerless ignition coil, one said I need a coil with 1.4ohm primary resistance, one said I need one with .7ohm primary resistance...

HELP!
Posted By: landon1

Re: Eliminating ballast resistor... What coil do I need? - 05/11/09 10:53 PM

idk about the pertronix systems, but i have electronic ignition and run 12V to an accel super stock coil without using the ballast resistor - no problems
Posted By: IronWolf

Re: Eliminating ballast resistor... What coil do I need? - 05/11/09 11:00 PM

Quote:

I'm replacing my old "F"d up electonic system with a petronics plug and play distributor system and would like to eliminate the ballast resistor as well. I was told that the old coils would fry if you ran them too long on 12 volts. I can't seem to get a straight answer out of anyone else as to which brand and model of stock appearing coil I need for this. One person said I need a breakerless ignition coil, one said I need a coil with 1.4ohm primary resistance, one said I need one with .7ohm primary resistance...

HELP!



The Factory Service Manual specifies .5 - .6 ohms.
Good luck finding those ! Most are 1 ohm or more, which is OK.

I have a .25 ohm resistor, that I keep around for "special occasions".

If you think about Ohm's law and electronics at all, you will realize why , in these special moments, less is more. Good luck.
Posted By: Anonymous

Re: Eliminating ballast resistor... What coil do I need? - 05/11/09 11:39 PM

For most stock type systems, and by that I mean points, Mopar ECU, or Pertronics (switching) eliminating the ballast is a BAD idea, here's why:

The entire reason that ballasts are used is to do at least two things:

They help to regulate current through the coil with changing rpm and voltage changes, IE lower voltage at idle, higher at cruise, and.....

one more very important function is that coupled with a bypass circuit for starting, this gives you a nice hot start under cranking conditions.

To my knowedge, there ARE NO old school, coil/ switching type systems, with the possible exception of the GM HEI which do NOT use a resistor in the ignition.

All it takes is just one cold dark night, a little humid, and you and your "girl" have listened to the stereo a little too long, and now the cranking speed is a little slow, and you top things off by nearly flooding the engine. So there you are, the spark is weak............
Posted By: RapidRobert

Re: Eliminating ballast resistor... What coil do I need? - 05/11/09 11:51 PM

Quote:

All it takes is just one cold dark night, a little humid, and you and your "girl" have listened to the stereo a little too long, and now the cranking speed is a little slow, and you top things off by nearly flooding the engine. So there you are, the spark is weak..

Sounds exciting. I ran the big yellow Accel super coil w no ballast(hei module) & no problems & didn't know at the time that I needed one .
Posted By: scratchnfotraction

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 12:11 AM

thats why I ran a #12 standed wire in the ballest shell with the stock ends solderd on

to hide the fact it was bypassed in the ballest shell

then I got rid of the old point style volt reg and used a new replacement style soild state vr and solved the prob with the alt dis charging at idle speed

stoped the alt gauge from jumping around and was steady after that

and the pertronix unit works better with a full 12volt and the matching coil

never had a problem with the old 68 1 wire alt/charging system or the points ignition system after those 2 conversions

I swap out the elect ecu crap on all of my smoggers and drop in the points dist with a pertronix coversion in it,leaves everything wired up and in place,cant tell exept for the 2 wires from the dist right to the coil

the points dist has a better adv curve stock as well for a little added help in a smogger,IMO

thats my hickabilly shade tree fix anyways

oh!,I ran the 68 with the ballest and it cut the 12volt back to seven or so,ran it 4 yrs that way and never had a problem with it,but it was lazy and sluggish.....but when I swaped it to a full 12 volt I could feel it in the seat of the pants and by the way it started first hit

runwhatyabrung

Posted By: RapidRobert

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 12:31 AM

Quote:

but when I swaped it to a full 12 volt it started first hit


that is what I saw w full 12V to the supercoil, it was unbelieveable, I would touch the key to start let go & it'd be running before the key snapped back.
Posted By: Pacnorthcuda

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 12:52 AM

Quote:

For most stock type systems, and by that I mean points, Mopar ECU, or Pertronics (switching) eliminating the ballast is a BAD idea, here's why:

The entire reason that ballasts are used is to do at least two things:

They help to regulate current through the coil with changing rpm and voltage changes, IE lower voltage at idle, higher at cruise, and.....

one more very important function is that coupled with a bypass circuit for starting, this gives you a nice hot start under cranking conditions.

To my knowedge, there ARE NO old school, coil/ switching type systems, with the possible exception of the GM HEI which do NOT use a resistor in the ignition.

All it takes is just one cold dark night, a little humid, and you and your "girl" have listened to the stereo a little too long, and now the cranking speed is a little slow, and you top things off by nearly flooding the engine. So there you are, the spark is weak............



Trying to follow this logic....but remember--the Mopar wiring DOES, as you state, provide a fUll battery power start during cranking by bypassing the BR.
My point? So does eliminating the BR entirely!

I don't get how the mopar BR design that provides "a nice hot start" can be an advantage over other designs that do too.
Posted By: scratchnfotraction

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 12:52 AM



night and day and trouble free 9+ yrs now

I see yor logic also,the BR is bypassed while cranking so its getting the full 12 volts...but mine was still sluggish and had to crank over1-2 times before liting off and running

same with the 85 truck after a intake a carb swap and the points dist droped in fires right up instant..would crank over 2-3 full turnes then fire off and run

I reachin and hit the key its running like RR said..before the key snaps back

I havent really looked any further as it works for me

Posted By: RapidRobert

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 01:02 AM

yes I would have been getting the same voltage(& I'm sure not 12)at the super coil w no ballast as with our ballasts which are bypassed. I lost it there on that one for a brief period of time but that easy starting was nice.
Posted By: Dusted_Ya

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 01:13 AM

Thanks guys! I FINALLY got ahold of tech support at petronix... They said you need an internally resisted coil (eg: the petronix flame thrower II or accel super coil or others) and then just wire the dis to the coil and a keyswitched hot and your good to go. no overheating problems and very little power loss when the key is left on and engine is off I guess the new flamethrower 2 or 3 automatically senses driving conditions and adjusts the advance automatically. That's freaken awesome! He said with the plug and play billet dist. or the points converter and the new coil the spark's so freaken hot you can open up sparkplug gap for better flame travel increasing HP and fuel economy! I'm starting to like this new technology stuff!
Posted By: scratchnfotraction

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 01:15 AM

I would not go to far on the gap

anything over 45 on mine used more fuel

back at 40 the mpgs came back

results may vary
Posted By: RapidRobert

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 01:18 AM

Quote:

They said you need an internally resisted coil (eg: the petronix flame thrower II or accel super coil or others)

So I didn't need a ballast w that big yellow Acell super coil after all. someone said that I did
Posted By: 6PakBee

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 01:21 AM

Quote:

For most stock type systems, and by that I mean points, Mopar ECU, or Pertronics (switching) eliminating the ballast is a BAD idea, here's why:

The entire reason that ballasts are used is to do at least two things:

They help to regulate current through the coil with changing rpm and voltage changes, IE lower voltage at idle, higher at cruise, and.....

one more very important function is that coupled with a bypass circuit for starting, this gives you a nice hot start under cranking conditions. ...........



Almost a direct quotation from the FSM.
Posted By: scratchnfotraction

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 01:24 AM

Posted By: 70Cuda383

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 02:06 AM

Quote:

For most stock type systems, and by that I mean points, Mopar ECU, or Pertronics (switching) eliminating the ballast is a BAD idea, here's why:

The entire reason that ballasts are used is to do at least two things:

They help to regulate current through the coil with changing rpm and voltage changes, IE lower voltage at idle, higher at cruise, and.....

one more very important function is that coupled with a bypass circuit for starting, this gives you a nice hot start under cranking conditions. ...........




yea, but it's that whole "COUPLED WITH BYPASS" that gives you a "nice hot start"

why wouldn't the "permanent bypass" give you "continuously nice hot ignition"?


from what I understood, stock coils would burn up because they were designed to operate at LESS than 12V, because they needed to be able to function while the engine is cranking, and they are seeing LESS than 12V anyway.

when cranking, and the starter motor is taking all that battery power up, there might only be 7-9 volts available to fire the coil, so they design it to operate at 7-9 volts. ok, now that the engine is running, alternator is making power...system voltage is up to 13 or 14...now we're nearly doubled what the coil is meant to see...and it needs stepped down...enter, the Ballast Resistor!

at least, that's how it was explained to me by an "old timer"

and from reading literatre from today's ingition folks like MSD, they have coils that are designed to operate on the full 12-14v system without needed the BR--I don't know if that's because they decided to sacrifice start up ability for driving performance (a coil meant for 12-14V that's only getting 7-9, won't fire as hot at start up) or if the change was because today's modern batteries don't experience as much of a voltage drop at start up as older batteries, or if the average starter motor today is more efficent...but if you read their tech info, they will tell you most of their coils can be run without a BR.
Posted By: Pacnorthcuda

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 02:15 AM

The first time I pulled a wire from the cap of my 440 (with an MSD 6AL and a Blaster E-coil) while it was running I was AMAZED. THATS LIGHTNING FOLKS! Far more energy than I have ever seen on any stock ignition. We're talking CRACK CRACK CRACK with arcs easily 1/2 inch or more long. Not a weak little snap snap snap.
There is no comparison.

I have a MUCH higher level of respect for avoiding getting zapped with capacitive discharge ignitions.
Posted By: Anonymous

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 02:27 AM

Quote:

The first time I pulled a wire from the cap of my 440 (with an MSD 6AL and a Blaster E-coil) while it was running I was AMAZED. THATS LIGHTNING FOLKS! Far more energy than I have ever seen on any stock ignition. We're talking CRACK CRACK CRACK with arcs easily 1/2 inch or more long. Not a weak little snap snap snap.
There is no comparison.

I have a MUCH higher level of respect for avoiding getting zapped with capacitive discharge ignitions.



An MSD (remember it stands for MULTIPLE SPARK DISCHARGE) has nothing at all to do with stock ignitions that is, "switching" types such as the MOPAR ECU or Pertronix
Posted By: Dusted_Ya

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 02:31 AM

I think the old style coils were designed and built on the technology of engines that operated on 6 volts continuously. 12 volt starting systems came about because of the lower line losses and highter efficiencies of a higher voltage. most gauges will operate from 3-48 volts fine but they used a constant voltage regulator to keep them accurate. The Coils on the other hand could operate only briefly at 12volts before overheating and meltdown.
Posted By: Pacnorthcuda

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 02:31 AM

Quote:

Quote:

The first time I pulled a wire from the cap of my 440 (with an MSD 6AL and a Blaster E-coil) while it was running I was AMAZED. THATS LIGHTNING FOLKS! Far more energy than I have ever seen on any stock ignition. We're talking CRACK CRACK CRACK with arcs easily 1/2 inch or more long. Not a weak little snap snap snap.
There is no comparison.

I have a MUCH higher level of respect for avoiding getting zapped with capacitive discharge ignitions.



An MSD (remember it stands for MULTIPLE SPARK DISCHARGE) has nothing at all to do with stock ignitions that is, "switching" types such as the MOPAR ECU or Pertronix



Except that it provides a nice hot spark(s) (Multiple at 3000 or less RPM) in ALL conditions.
Posted By: Anonymous

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 02:41 AM

Quote:

yea, but it's that whole "COUPLED WITH BYPASS" that gives you a "nice hot start"

why wouldn't the "permanent bypass" give you "continuously nice hot ignition"?



You're helping to prove my point. Back to a "stocker" example, the coil is ......

DESIGNED TO OPERATE on the SAME VOLTAGE whether cranking (10-11v)..... or running through the ballast.

This means that in theory, you should have the SAME HOT SPARK whether cranking / resistor bypassed, or running (charging) through the bypass

When bypassing the resistor, AND USING a coil designed for direct connection to 14v (not 12) you must now DROP that voltage clear down to 10-11V or so for CRANKING.

THAT IS a 28% change in voltage!!!


Quote:

and from reading literatre.......... like MSD, they have coils that are designed to operate on the full 12-14v system without needed the BR--I don't know if that's because they decided to sacrifice start up ability for driving performance (a coil meant for 12-14V that's only getting 7-9, won't fire as hot at start up).




Exactly my point of the "cold dark night" example. When everything is great, well, it's great. It's for those times when it's a little cold and humid, or you've flooded the engine, or the battery is a little low, etc etc, or maybe the engine is a little hot and balky. THAT is when you need that extra kick.

I SAY that unless you are running a CD/ MSD type ignition, that is, you are running points or switching electronic, you will have MUCH better overall start performance by using a system designed for and with a ballast.

I think some of you are confusing the use of a ballast with low performance. Remember the big huge Mallory rectangular coils? Those used TWO ballasts---the original OEM, and an additional one supplied by Mallory--in series. They certainly were not "low performance."
Posted By: Dcuda69

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 03:05 AM

I think what gets lost here is the fact that not only does the coil need to withstand the additional voltage,so does the switching device! Take a 1 ohm coil,at 9 volts, when the switching device(points,ecu,etc)turns on(pulls coil- to grd)the current flow thru the pri. windings(and the ecu)=9 amps.Same 1 ohm coil at 14 volts,when turned on(coil- to grd.thru the ECU) will flow 14 amps!Remember(on a v-8) the coil has to fire every 90 deg. of crank rotation!Current flow=HEAT!But that heat affects not only the coil but the switching device!!!If you want big spark,switch to a MSD type ign. Big reason the OEM's went to COP,more charge time and more cool down between firing!I wonder if all the failed ECU's are due to wiring issues more than quality control?
Posted By: 383man

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 04:41 AM

This is the yellow Acell Super Coil I use on my 63 with the MP orange box and it calls for the .75 ohm ballast which I use. We also used it on my boys Dart before he put the MSD unit on it. It went no faster when we put the MSD on the car and my 63 never misses a beat using the .75 ballast. The ballast controls the current flow thru the coil and control unit or points. At low speeds when the dist is turning slower and there is more dwell time the ballast heats up and drops coil output but at higher speeds when the dist is turning faster and there is less dwell time to heat the ballast the ballast cools off and the resistance goes down some to increase the coil output when needed. I have seen guys burn the chrome MP box up from using the wrong or no ballast. And when I bought that same yellow Acell Super coil back in the 70's for my dual point dist you got and extra .25 ohm ballast to add in series with the stock ballast so it would not burn the points up. All I am saying is be careful if you bypass the ballast on an ign system set up to use it or you may burn the coil or control unit out. Ron

Posted By: MoPar Jamie

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 05:14 AM

OK on my lameburn Diplomat STOCK there was NO resitor present at all. I unwrapped the engine harness to make it simple to plug right into the main harness when I converted to electronic. I found the coil wire was spliced directly into constant (not start) 12v hot. I also looked at my D-250 and its the exact same way.

So when I converted it I ran a two-wire ballast connector, one to the switched 12v blue wire and the other to the coil positive. I resisted the ignition box power wires like stock. Coil is the original one to the car.

So, am I going to run into problems down the road?
Posted By: Anonymous

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 05:39 AM

Quote:

OK on my lameburn Diplomat STOCK there was NO resitor present at all. I unwrapped the engine harness to make it simple to plug right into the main harness when I converted to electronic. I found the coil wire was spliced directly into constant (not start) 12v hot. I also looked at my D-250 and its the exact same way.

So when I converted it I ran a two-wire ballast connector, one to the switched 12v blue wire and the other to the coil positive. I resisted the ignition box power wires like stock. Coil is the original one to the car.

So, am I going to run into problems down the road?



I'm not familiar with "lameburn" so unless you can post a link to a diagram, don't know.

Ron posted an excellent example of a great running car that so far's I'm concerned, is one way to set things up properly.
Posted By: radar

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 02:12 PM

Are you serious or just being funny? I am new to mopars and I know about the lean burn emissions package- tons of extra crap to make you crazy bolted and wired up to the motor...
Posted By: Anonymous

Re: Eliminating ballast resistor... What coil do I need? - 05/12/09 02:28 PM

Quote:

Are you serious or just being funny? I am new to mopars and I know about the lean burn emissions package- tons of extra crap to make you crazy bolted and wired up to the motor...



When I say I'm not familiar with leanburn, I mean I'm not familiar--WITHOUT REFERRING TO A MANUAL--on how or how not the ignition system is wired up.

(Making the statement that "it has tons of extra crap" etc, is something I could have said. that doesn't mean you know how it works, or can itemize wiring points of interest off the top of your head.)
Posted By: radar

Re: Eliminating ballast resistor... What coil do I need? - 05/14/09 04:32 PM

gotcha. I only know how to take it all off I couldn't make it work right or explain anything. not trying to be holier than thou!
Posted By: Dart 340

Re: Eliminating ballast resistor... What coil do I need? - 05/14/09 05:22 PM

Be careful with Pertronix and removing the BR. They
only recommend it with the Ignitor II and III NOT
on the original Ignitor. The original will burn up
if you remove it.
Posted By: 64Post

Re: Eliminating ballast resistor... What coil do I nee - 05/14/09 06:36 PM

Quote:

Be careful with Pertronix and removing the BR. They
only recommend it with the Ignitor II and III NOT
on the original Ignitor. The original will burn up
if you remove it.



Correct.

You need to do a loaded voltage test to determine if there is enough juice at the coil. I'm going through this process right now. I have the Ignitor II and I'm trying to incorporate their HV coil into the system. 8v is the minimum. I only have 3.6v at the coil with the BR, so that's not going to work.
Posted By: scratchnfotraction

Re: Eliminating ballast resistor... What coil do I nee - 05/14/09 07:43 PM

I used the shell of the BR and used the ends of the guts and solderd in a #10 strand wire

put it back in the shell,got a full 12 volts on the 68 dart

Posted By: 64Post

Re: Eliminating ballast resistor... What coil do I nee - 05/14/09 08:15 PM

Quote:

I used the shell of the BR and used the ends of the guts and solderd in a #10 strand wire

put it back in the shell,got a full 12 volts on the 68 dart





That's what I'm in the process of doing...

But my butter-fingered DA dropped the OE BR last night and I had to find a new one.
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