ELECTRONIC IGNITION UPGRADE

[Anonymous-0]

thinking about updating my old points on a 1950 mt to an electronic ignition conversion. who has the better product? anyone notice considerable differences? and how many different manufacturers are there for these units? i've found two so far. thanks in advance as always

 

[John T]

Regardless if you go with Pertronix or anyone else, to get the most bang for the buck and utilize the advantages the elec switch has to offer, I highly recommend you also match up the switch with a high energy high voltage coil (versus a stock coil) and you can run a wider plug gap and discharge more energy across a wider plug gap for a hotter more surface area spark Woooooooo Hoooooooooo. Make sure to match the polarity (Pos or neg ground) so you dont let the smoke out of that new expensive switch now grrrrrrrrr and Id use good quality plug wires and cap etc at those higher voltages....

John T

 

[Anonymous-0]

Get the upgrade, it will be worth it. Buy it from one of the advertiser's out of Green Magazine. They are all about the same price. I'm guessing your MT is a 12-volt not a 6-volt. From experience a 6-volt is very difficult to make this system work properly. If it is a 12-volt you will see a lot of improvements in every way the tractor runs and the tuneability. Good Luck

 

[Machinery-Man]

never tried it on 6 volt but many times on 12 volt and it is astonishing as to quality.

 

[Anonymous-0]

The spark jumps the plug gap at about 10000 volts.The 40000 volt ignition is a fable...

 

[Bob]

Who has the better product????

What brands are you comparing?

Unless you go to an exotic "Hot Rod" ignition, Pertronix is the only game around.

There is another "brand" out there, but they are simply "private-labelled" Pertronix units.

 

[John T]

Sorry to be the bearer of bad tidings, but with all due respect THATS SIMPLY INCORRECT.....Heres the engineering correct explanation in as simple terms as I can make it:

The voltage necessary to arc jump current across a spark plug gap is a function of 1) The Medium (compression and fuel mixture) in which it fires and 2) The spark plug gap.

Therefore, as you widen the plug gap given the same medium (fuel and compression) it requires higher voltage for current to arc jump across the gap AND A HIGH VOLTAGE COIL (say a 40,000 volt capable coil versus a stock 10,000 volt rated coil) has the capability of achieving that higher voltage which the stock coil (say only a 10,000 volt ability) simply can not.

I think I can explain the confusion many laymen have when claiming it takes 10,000 volts to jump the plug gap and a high voltage coil would be a waste: Heres the deal, its indeed true that given the same medium (fuel n compression) and the same plug gap THE HIGH VOLTAGE COIL WILL STILL INDEED FIRE AT THE SAME VOLTAGE AS THE STOCK COIL which may typically be in the 7,000 to 10,000 volt range for say a 0.025 plug gap in a low compression (say 125 PSI) tractor. You see, the voltage only rises high enough to jump the gap AND NOT A VOLT MORE so at that same gap and that same compression, the super coil dont fire at any higher voltage then an old stock coil and just cuz the high voltage coil has the CAPABILITY to rise to 40,000 volts sure dont mean it will given the same plug gap n compression.

HOWEVER as you widen the plug gap beyond the distance a stock coil can produce a high enough voltage to arc current across, it will fail to fire the plug where the high voltage coil will fire the plug. If the plug gap is wider theres less heat quenching of the spark and you end up with a wider, hotter current arc having more surface area to better ignite the fuel THATS WHY HIGH ENERGY ELEC IGNITIONS USING HIGH VOLTAGE COILS CAPABLE OF ARC JUMPING CURRENT (AND MORE ENERGY) ACROSS A WIDER PLUG GAP (which the stock coil cant) INCREASES PERFORMANCE.

Now, again if the old stock coil was retained it will still fire provided the plug gap isnt increased beyond the voltage the coil can achieve and it will work buttttttttt to get the most bang for the buck that elec switch has to offer, if you couple it with a higher energy and higher capable voltage coil and use a wider plug gap (which only the 40,000 HV coil can fire) you get a wider hotter spark of more surface area to better ignite the fuel PERIOD.

Even if you leave the plug gap the same where the HV coil still only fires at 10,000 volts just like the old stock coil, theres still improvement with an elec ignition due to its improved current switching characteristics and the improved efficiency of the more modern high performance coils. Likewise, even with the old stock coil and the same plug gap the elec switch still gives better performance even if it only fires at the same 10,000 volts.

Hope this helps and yall take care n keep safe now

John T Retired Electrical Engineer

 

[Anonymous-0]

I spent many years working on color tvs that used 25000 volts.This voltage would jump a 1 inch gap with ease.When the voltage got up to 30000 volts there the arcing was bad, cracking glass around the anode connector and punching thru insulation.I would like to see 30000 true volts in an ignition system.All cylinders would fire at the same instant.The fuel charge in a cylinder either ingnites or goes out into the exhaust system.As long as the fuel charge ignites on a regular basis there is no advantage to increasing the spark voltage.High voltages do increase spark plug electrode wear.50000 volts will jump a 2 inch gap in free air.You will need some tall spark plugs and some fat insulation in the ignition system.

 

[Machinery-Man]

Per the discussion on the plug gap, I've used the electronic on 6 tractors and just used the plugs as is and it worked great. Plugs never fouled with the higher voltage and I would also recommend the matching coil. You need to be careful installing the donut and wiring....I used it on 50, 520's 530's 620. Used the kits from Petronix...the heart of it is the pickup sensor and the ring donut that goes over the distributor shaft. Also it powers with staight voltage so don't tie it through a resistor block...

 

[John T]

Good points (at atmosphere), HOWEVER, the voltage necessary to jump a same given distance INCREASES AS THE COMPRESSION IS RAISED i.e. at atmosphere it may only take say 5000 volts to jump a certain gap buttttttttttt at 120 PSI Compression it takes more voltage before current will jump that same gap. You simply cant compare or equate the voltage required to jump a gap at atmosphere with the voltage to jump the same distance gap under compression !!!!!!!!!!!!! LIKEWISE you cant say (and be correct lol) given the same conditions (pressure and medium) the voltage necessary to jump a spark plug gap doesnt have to be increaded as the gap widens.... High School Science and/Physics could explain that.

Next: One reason a high voltage coil is better in high energy electronic ignitions, is that it can achieve a higher voltage necessary to jump a spark across a WIDER plug gap which the stock coil simply may be unable (based on its voltage rating) to achieve. A spark across a wider plug gap with a HV high energy coil yields a wider more surface area and HOTTER spark (less heat quenching to the ground strap) and more energy discharge (volts x amps x time) which provides better combustion then when a low energy lower voltage (which cant arc too wide of a gap) stock coil and ignition is used.

SOOOOOOOOO its NOT a "Fable" that high energy high voltage coils and electronic ignitions running wider plug gaps FIRE AT HIGHER VOLTAGES then a stock coil points and ignition system with a narrower plug gap. Hey, even a stock coil fires at higher voltage as the gaps increased up until the point the gaps too wide for the coils voltage capacity...... The stock coil simply cant reach as high of a voltage as a high voltage coil can and it does take a higher voltage to arc current across a WIDER plug gap and if the gaps too wide a stock coil cant fire the plug. Those involve laws of physics and basic electricity that we cant break.

THE WIDER THE PLUG GAP THE MORE VOLTAGE REQUIRED TO FIRE THE PLUG PERIOD

THE WIDER GAP FIRES AN ARC ACROSS MORE DISTANCE IN THE COMBUSTION CHAMBER AND WITH A HIGH ENERGY HIGH VOLTAGE COIL (which can jump the wider gap) THE ARC IS HOTTER (less heat quenching) AND HAS MORE SURFACE AREA (throughout the combustion chamber) WHICH BETTER IGNITES THE FUEL PERIOD

SINCE IT TAKES MORE VOLTAGE TO ARC CURRENT ACROSS A WIDER PLUG GAP, A HIGHER VOLTAGE CAPABLE COIL IS USED AND IT OBVIOUSLY AND INDEED FIRES AT A HIGHER VOLTAGE THEN IF THE GAP WERE DECREASED PERIOD

Hey Im NOT here to sell or push electronic ignitions, Im just trying to help people and explain how n why an electronic ignitions and a high energy high voltage coil running a wider plug gap fires at a higher voltage and how it can better initiate combustion and improve performance and ITS SIMPLY NOT A FABLE DESPITE MANY LAY OPINIONS TO THE CONTRARY ........

If people want to use original equipment Im allllll for that but there is indeed performance to gained when using elec ignitions and high energy high voltage coils and wider plug gaps which necessarily (from laws of physics) require higher firing voltages.

BOTTOM LINE if you want originality and the Corect Police are a concern STICK WITH ORIGINAL POINTS N CONDENSOR AND STOCK COIL IGNITION

HOWEVER if you want improved performance AN ELECTRONIC IGNITION AND A HIGH ENERGY HIGH VOLTAGE COIL AND FIRING A SPARK ACROSS A WIDER PLUG GAP (or even the same gap due to still more energy dissipation) IMPROVES PERFORMANCE

Its the owners tractor and his choice and Im happy for whatever ignition he chooses to use but it still takes more voltage to arc a wider plug gap (inviolate laws of physics involved) and a high voltage coil is capable of achieving higher voltage then a stock coil.

Hope this helps explain elec ignition advantages for yall, great n fun discussion n yall take care now, best wishes. Its your tractor n your choice so be happy with whatever ignition you choose and again I COULD CARE LESS and am NOT an elec ignition salesman lol (nor here to argue, just state the engineering facts n theories then yall decide for yourself) despite this engineering explanation of their advantages


PS will check with yall later gotta take my dear old mother somewhere today then help an older buddy fix his Detroit Diesel grrrrrrrr


John T

 

[Rick Kaufmann]

I have a 1958 JD 530 2 cyl. 12 volt + ground that I think I want to add an electronic ignition system to over the winter. Spec plug gap is .030". If adding a HV coil as well, what plug gap would be appropriate? Do you stay with spec plugs or use some type of plug upgrade also? If so, any recommendations for plugs? Machinery-Man, you commented about not using an ignition resistor with the electronic system. The 530 has a 12 to 6 volt ballast resistor mounted up under the instrument panel. Do I need to inactivate this with the electronic ignition? Thanks for your advice.
Rick [/quote]

 

[Bob]

You HAVE to use a resistor appropriate for the COIL you are using, to limit primary current to 3 to 4 Amps.

If you don't, all the $$$$ smoke will very quickly leak out of your new Pertronix unit.

HOWEVER, the power wire for the actual Pertronix MODULE gets connected AHEAD of any resistor used, to supply full battery voltage to the MODULE. (It's in the Pertronix instruction sheet.)

 

[Bob]

How does this sound to you?

The voltage needed to ionize the mixture in the spark plug gap and make a spark is determined by the width of the gap, the amount of compression, and, to some degree, by the mixture... a LEAN mixture will require more voltage to "fire the plug", other things remaining the same.

In other words, those factors, rather than the theoretical voltage of the coil, determine the voltage at which the plug actually "fires".

 

[John T]

Rick, NORMALLY (dont have to) when you upgrade to an elec ignition switch and provided you also upgrade to a high energy high voltage coil (as I recommend) you run a wider plug gap then that specified for the stock points n condensor ignition system. As the plug gap is increased it takes more voltage to arc jump current across it so if you have the elec switch and high voltage coil thats capable of bridging that wider plug gap, you end up with a wider more surface area HOTTER (less heat quenching to ground strap) spark to better ignite the fuel. Check with the vendor (depends on coil n switch specs) but its not uncommon to use instead of a 0.025 t0 0.030 stock plug gap to use more like 0.035 to 0.045 or more with an elec ignition and a HV coil.

You would still use an external voltage dropping(12 to 6) series ignition ballast resistor if you wanna use a 6 volt coil on a 12 volt tractor like many stock tractors were equipped HOWEVER you can use a straight full true 12 volt coil NO BALLAST REQUIRED andddddddddd they make those after market high energy high voltage coils (Pertronix Flame Thrower or MSD etc) rated full 12 volts SO NO BALLAST IS REQUIRED. Thats how I recomemnd in my seminars you do it if you upgrade, is to toss any stock 6 volt coil and use a 12 volt high energy high voltage coil NO BALLAST REQUIRED WHATSOEVER.

Be sure n match the switch polarity with the tractors and you can still use a 6 (with ballast) or a 12 volt coil so its your choice butttttttt if you use an elec switch and a high energy HV coil and run a wider plug gap she ought to perform better...........

John T

 

[John T]

Bob, YOURE EXACTLY RIGHT (we bout always agree) regarding "other then theoretical factors" determine the firing voltage (in my opinion at least)

Thats why I said the voltage required to arc jump current across a spark plug gap depends on 1) The Medium ("fuel" n compression) in which it fires PLUS 2) The gap distance. I STAND PAT ON THAT AND LOOKS LIKE WE AGREE as what I call "fuel" equates to what youre talking about in the lean versus rich "fuel" mixtures.

When racers start running some of those exotic fuels they can also require different firing voltages then regular old 87 octane.......Plus they are at extreme high compression requiring even higher voltages to jump the same plug gaps

As far as your thinking it would require more voltage to fire using a LEAN mixture we need to discuss that more n I need to think on it some. Heres my initial thoughts I will toss out for discussion: We would agree at higher compression more voltage is required right??????? And at higher compression theres more molecules more density in the area between the plug tip and ground strap right?????? BUTTTTTTTTTTT at a LEAN mixture theres more oxygen molecules then fuel molecules (lower fuel to air ratio) right i.e. thats why its called a lean mixture right ???

SOOOOOOOOOO MY QUESTION FOR DISCUSSION WOULD BE is it easier to arc current through fuel molecules or oxygen molecules ?????????

If its easier to arc thru fuel molecules, looks like a RICHER mixture requires less firing voltage and a LEAN mixture higher voltage KINDA LIKE YOURE THINKING butttttttttt if the opposite is true that its easier to arc thru oxygen molecules then fuel, then Id expect a lean mixture to require LESS firing voltage.....less difficult fuel in the way to get through

However I can see how if were NOT talking about arcing current the fuel atoms may be better conductors then air (known poor conductor) so theres less resistance, but when we talk about arcing and ionization that creates the current path, there can be more to it.



YOUR THOUGHTS PLEASE
WE NEED TO DISCUSS "IONIZATION" MAYBE

Great discussion Bob, sorry if we bore the other non sparkies lol but we BOTH seem to love this tricity chat

Take care now, I will check back later

John T

 

[John T]

Bob, Good points, I gotta peruse some Pertronix specs n data. If I recall (been a while since I looked) correctly they make elec switches of different current ratings (one for their basic coil and a higher current rated switch for their higher energy coil) so he has to be sure n match the coil with the switch, but it look like Pertronix should advise him on that choice.

Gotta look at Pertronix info

John T

 

[Bob]

Connect an ignition scope to an engine mis-firing due to an air leak in the intake system, and you can often pick out which cylinders are affected by the air leak (lean mixture) 'cause the firing voltages are "spiked up" on the offending cylinders.

 

[Mike Aylward]

Just to add to John and everyone's good advice, I usually run about .040-.045" gap on the standard plugs when I do a conversion. That is about all they can be opened up and still allow the outside to remain parallel to the center electrode. I have installed 14mm adaptors to other tractors and used current automotive plugs and ran a wider gap on them (such as pulling tractors) but used a hotter system for that with the Pertronix unit to do the triggering. Hope this helps. Mike

 

[buickanddeere]

Even the stock coil will perform better with electronic switch. The voltage spike and energy is higher when the primary current is cut instantly. Points always arc some and dribble away some of the coil's stored energy.
The plug gap has to be opened way up to show improvement. Some electronic systems require "resistor" wiring. No problem, there are solid core wound conductor wires. Just use one between the coil & dist.
Solid wires everywhere else and non resistor plugs.
The only real limit on spark plug gap if its way too wide. The spark inside the dist eventually jumping off the rotor and onto other metal inside.
That's why auto manufactures have scrapped the dist for individual coil packs. The plugs can be worn to nubs and the coil will still jump a spark across reliably.
In fact a gasser 20 or 30 series two cylinder with the 1/2 speed dist will run fine with just the points/electronic module and a dual coil pack. No rotor or cap required.

 

[Mike M]

I'm the odd man out evidently ? I still run points and 6 volt systems and don't seem to have any problems with it ? I just see it as part of the appeal of having an old tractor.

 

[RandyB(MI)]

My hat's off to John T. for his wealth of tech advise and wisdom he brings to this forum. His explaination just above is right on the money. I only have to add one thing to the last part of his post about even if all you do is upgrade the "switching devise" and nothing else you will see a difference. I dissagree in this case. On a "stock" 2 cyl. JD with stock ignition that is new and adjusted correctly you will not see or feel in the seat of your pants any diff. after installing only the E.I. "switch". On the other hand, if you are going to farm every day all summer long with this tractor (doubt it) it will stay fresh without adjustment or cleaning etc longer that the original. I believe most of the people who are inquiring about these systems on this forum really need one like another A-hole. You are not gonna "feel" it! It's not like adding a four bbl. carb to a two bbl. engine! My oppinion on them is this. If you have EVERYTHING else on the tractor blueprinted,ballanced and adjusted perfectly and every system is performing as close to 100% as humanly possible , then by all means I would add one of these just to get that last .00028% because it may just get you by that one last tractor at the pulls. Let's be serious here , there are bound to be places on or in that tractor that you could put that money and be able to actually "feel" it when your done. If your tractor could ask for anything it wanted for Christmas , trust me , EI would be towards the end of the list.

 

[Duane Larson]

I'm getting in late here, but a great discussion. John T, you have the essentials, but things are a bit more complicated - just what you needed, right??. The air-fuel mixture in the spark gap is an insulator, and so has a property called a dielectric strength. That is the voltage required for establishing an arc in the gap, and usually has units of volts per millimeter, or kV/cm, or some such. Several factors affect the ability to establish the arc, including:
1) the size of the gap
2) the shape of the gap electrodes (that is why filing the center electrode so the edges are sharp lowers the required voltage - having sharp pointed center electrodes and ground straps would really lower the required voltage, but the plug would have a short life)
3) the density of the air-fuel mixture (higher voltages are required when the throttle is wide open and more air/fuel is flowing)
4) conductive contaminants on the insulator cause the spark to occur at places in the plug other than across the gap
5) the temperature of the electrodes - higher temperature reduces the required voltage
6) how fast the voltage increases - that is a real advantage of the electronic ignition as it lessens the effects of any leakage of high voltage
7) the air-fuel ratio - defines the value of the dielectric strength - as noted, higher values of the a/f ratio (lean mixtures) have higher dielectric strengths
8) electrode material and polarity - center electrodes made of platinum or iridium alloys are better at emitting electrons, and starting the arc process

Some of these have been touched on - others haven't. Anyway, interesting thread! Glad also for the "Modern View" system available now so entries to this thread don't get lost - although perhaps some folks think this one should have....

 

[Anonymous-0]

Adding an expensive part to a tractor is a downgrade.I put up 200 bales of hay with my tractors this week.The points were replaced 15 years ago.I check the gap when the spring work starts and forget them.An electronic ignition module failure would be a disaster moneywise.Twine is running 35.00 a bale, gas at 2.80.Just paid 24.96 for a pitman stick.Aint no money left for ignition modules.My tractors start and get the work done without 100.00 plus ignitions.The JD H is on its 2nd set of points in 42 years.It starts in about 2 turns of the flywheel.All ignitions are electronic any way.I find keeping good clean spark plugs in the tractors keep them starting well.