Ballast Resistor Wire

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erco
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Ballast Resistor Wire

Post by erco »

I read plenty about removing/bypassing the ballast resistor to run a Pertronix ignition. The pseudo ballast resistor is actually a wire inside the wiring harness on my LM ('67). Has anyone detailed where the wire is and/or how to bypass?

TIA

66vairguy
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Re: Ballast Resistor Wire

Post by 66vairguy »

erco wrote:
Wed Sep 02, 2020 2:25 pm
I read plenty about removing/bypassing the ballast resistor to run a Pertronix ignition. The pseudo ballast resistor is actually a wire inside the wiring harness on my LM ('67). Has anyone detailed where the wire is and/or how to bypass?

TIA
WHICH PERTRONIX??? I've fixed so many incorrectly installed Pertronix kits I've come to the conclusion the instructions are lacking for most.

NO DON'T BY-PASS THE BALLAST RESISTOR!!!! This is only done with the Pertronix Ignitor II and the 0.5 ohm Flamethrower coil. The Ignitor II has had issues with mis-firing at low RPM in a Corvair, especially on PG cars that have a lower idle in "Drive" vs the manual transmission cars. This problem has been well documented for years and Pertronix isn't going to fix it. Despite "claims" the Ignitor II and hot coil do NOT improve performance for the non-turbo Corvairs. Don't waste your money.

Yes you should use a full ignition switched 12VDC to power the Petronix (red wire). Some use power from the coil "+" terminal via the ballast, but I don't recommend doing that. In 67 the Corvair wiring changed - so use the correct wiring diagrams.

The most reliable set up is the Petronix Ignitor (some call it Ignitor I) with a STOCK coil and ballast. All you need to do is replace the points and re-set the timing. I've had too many issues with Pertronix Flamethrower coils and won't use them. The stock Corvair coil is a better impedance match. If you need a new coil buy a quality brand coil that for a 1965 Chevy small block V8 (283 or 327c.i.). The FLAPS stock the cheapest coil so you usually have to order the premium version. The Corvair 140HP coil and the Chevy V8 coil were very similar. If you ask for a Corvair coil either it's not listed or is the one for the low HP engine and not recommended for the 110HP or 140HP engines. Do make sure you install the ground wire between the moving parts of the new module plate. I've had a few Pertronix kits that were missing the ground wire and other parts.

BTW - if the distributor shaft has too much side to side play the bushing will have to be replaced - easy if you have the knowledge and skills. DO NOT use the Clark's double bushing rebuilt distributor. This "mod" has been found to cause expensive problems sometimes and the the single factory bushing will last well past 50,000 miles. This incorrect idea was to emulate the V8 distributor, but the Corvair engine uses the oil pump housing as the second bushing. So the mod results in THREE bushing and invertibly one won't line up with the other two and the shaft binds - not good.

BTW if your engine has a 1967 distributor - find and install a 1965 unit - better curve as 1967 was the start of emissions timing.

And finally ----- gap the spark plugs to the shop manual spec. Most new plugs are gaped too wide for use with modern ignition systems.

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bbodie52
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Re: Ballast Resistor Wire

Post by bbodie52 »

Probably the easiest way is to identify the wire that brings the ignition voltage from the ignition switch to the coil with the key in the ON position. This wire enters the large multi-connector in the engine compartment. A that point it has full 12 VDC available when the key is in the ON position. on the other side of the connector, the same circuit exits the multi-connector and enters the resistor wire. The output of the resistor wire connects to the two-connector plug that connects to the starter solenoid. The wire is spliced at that point and continues on to the ignition coil input (positive terminal). When the solenoid is not active, the reduced resistor wire voltage passes via the spliced connector to the coil. When the starter solenoid is engaged, 12 VDC is applied to the same wire (from the solenoid), which overrides the reduced resistor wire voltage and temporarily applies full 12 VDC voltage to the coil (to provide a "hotter" spark plug voltage to help start a cold engine).

If you go back to the large multi-connector and tap into the wire from the ignition switch (on the firewall side of the multi-connector) you can pick up the 12 VDC from the ignition switch there and run a straight bypass wire to the coil positive terminal. This bypasses the resistor wire circuit and the starter solenoid output connection.
bbodie52 wrote:The illustration below shows the point where you can tap in to the existing engine compartment wiring harness to bypass the existing ballast resistor circuits and provide a direct tie to the ignition switch 12 VDC power source for an aftermarket electronic ignition system that requires 12 VDC full-time. 1962, 1964, and 1965 Corvair harnesses are shown...

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1965-1969 Corvair Engine Compartment Multi-Connector

As far as I know, the Crane Cams optical trigger XR700 is the only unit that is designed to have its electronics run on a voltage source that has already been lowered by a ballast resistor. In fact, the instructions state that connecting the Crane Cams electronic unit to a full 12 VDC power source may cause it to overheat and begin to malfunction.

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Pertronix Ignitor Specifications
Operating Voltage: 8-V to 16-V DC

According to Pertronix, the Ignitor can operate with an input voltage power source of 8-16 V DC. The ballast resistor in the Corvair primary circuit will drop the 12-14 V DC seen with the engine running and the alternator charging down to approximately 7-9 V DC. So if you are tapping voltage for the red Ignitor wire at the coil positive terminal, you are already close to the minimum tolerable specification. Active circuits in the car such a headlights, the heater fan, etc. can draw the average voltage down.

The stock Corvair Delco coil is also designed to run on continuous voltage that has been reduced by a ballast resistor or resistor wire. The Corvair circuitry is designed to feed the stock coli a full 12 VDC briefly from the starter solenoid while the engine is being cranked, which boosts the secondary output voltage to the spark plugs to help get the engine started during cranking. But the voltage to the coil is reduced by the ballast resistor wire in the harness to a nominal 7-8 VDC as soon as the key is released and the starter solenoid disengages. This lower voltage helps the ignition coil to run cooler, yet still produces a spark that was deemed adequate by GM engineers for normal engine operation. The reduced voltage also helps to prolong the operational life of the ignition points by reducing arcing and burning as the points open and close.

Most high performance aftermarket ignition coils — such as those produced by Crane Cams and Pertronix — are designed for higher voltage output to the spark plugs, and are designed to handle a full 12 VDC power source during continuous engine operation without overheating.

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HOWEVER, THE PERTRONIX FLAME-THROWER COIL IS AVAILABLE IN BOTH 1.5 OHM AND 3.0 OHM VERSIONS. PERTRONIX RECOMMENDS A FULL 12 VDC INPUT WITH NO EXTERNAL BALLAST RESISTOR FOR THEIR FLAMETHROWER COILS, BUT ALSO RECOMMENDS THE 1.5 OHM VERSION FOR V8 ENGINES AND THE 3.0 OHM VERSION LISTED BELOW FOR THE 4 AND 6 CYLINDER ENGINES.

The 3 ohm version of the Flame-Thrower coil reduces current flow through the primary winding, which causes the coil to run cooler with the longer 4 and 6 cylinder engine duty cycle (the amount of time the coil primary winding is ON between ignition firing cycles). This average charging time before discharge to fire a spark plug is longer at a given RPM on a 4 or 6-cylinder engine due to the reduced number of cylinders. The coil is able to produce its advertised 40,000 volt output with a reduced current 3.0 ohm primary winding and an associated reduced current flow, which allows the coil to run at a cooler temperature. The duty cycle with an 8 cylinder engine is shorter, so the 8 cylinder engine needs more current flow through the coil from the 12 volt input, therefore a 1.5 ohm primary is specified for an 8 cylinder engine.

In either configuration, bringing a full 12 VDC to the coil positive terminal provides a convenient power source for an electronic ignition, such as a Stinger distributor or a Pertronix Ignitor or Ignitor II module. This would not be recommended for the Crane Cams XR700 electronic ignition module, however, since it is designed to operate with a voltage that has already been reduced by a factory ballast resistor or resistor wire.


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40611 Black Epoxy Filled Flame-Thrower 40,000 Volt Coil — 3 Ohm

28010 Black Industrial Oil Filled Flame-Thrower 40,000 Volt Coil — 3 Ohm

40511 Black Oil Filled Flame-Thrower 40,000 Volt Coil — 3 Ohm

40501 Chrome Oil Filled Flame-Thrower 40,000 Volt Coil — 3 Ohm

:angry: :nono: Note that it is never wise to leave the ignition key in the ON position for a long time without the engine running. If the points are closed or the electronic ignition module is conducting electricity continuously to Ground from the coil negative terminal without the engine running, the battery will be draining and the coil may overheat and possibly be damaged. Some early Pertronix Ignitor I electronic modules were also known to be damaged if the key was left ON without the engine running.
Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible

plrgpr
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Re: Ballast Resistor Wire

Post by plrgpr »

66vairguy, see photos. My car definitely hast the electronic ignition installed. This is apparently what I have installed on my 66 140 4-sp. I say apparently as I’ve had the car for only 1 1/2 yrs and these boxes, with the OEM parts inside came with an assortment of parts along with the car. Brad indicated that I should have the 3 ohm coil, but appears I have the 1 1/2 ohm. Two wires from the distributor, red one is on the positive side. I say all this to say that the distributor rotor failed and left me stranded a few weeks ago cruising down the road at 60 mph! The inside of the cap was coated with goldish colored filings (same color as the end of the rotor) and the end of the metal contact on the rotor burned off which, I assume, ultimately caused the engine to quit. I have no idea how many miles were on the rotor, I’ve put a couple of thousand on the car since I’ve had it. Do you think that the electronic conversion had anything to do with the rotor failure? Do I have the proper system installed on my car?
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Gary Roberson
66 Vert 140 4-sp Corsa “clone”

erco
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Re: Ballast Resistor Wire

Post by erco »

Thanks for all the info, 66vairguy & Brad. My distributor is in good shape and has had work done to it over the years. Many new parts, including advance weights & springs. My car is a '67 Monza with a 140 transplant but I always built the engine as a '66 to avoid smog stuff.

I bought the Pertronix 1 based on recommendations from the manufacturer. I plan to run my existing Bosch "big blue" coil, which has a resistance of 3 ohms. Based on what I've read, bypassing the ballast resistor wire is in order.

TTYTT I'll probably start out with a stock set of points just to minimize variables on this 140 engine which hasn't run in 20 years. Then switch to Pertronix later.

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terribleted
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Re: Ballast Resistor Wire

Post by terribleted »

It is a good plan to get it going well stock before switching to the electronic ignition, that way if there are issues blaming the electronic ignition unit is not an issue.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

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bbodie52
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Re: Ballast Resistor Wire

Post by bbodie52 »

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This Pertronix Flame-Thrower coil is the 40,000 Volt Output 1.5 ohm version (P/N: 40011).
The recommended coil for a six cylinder engine is the 40,000 Volt Output 3 ohm version (P/N: 40511). The fewer number of cylinders means a six-lobe Corvair distributor cam instead of the 8 lobe cam in a V-8, which translates into a longer duration of time at any given RPM that the points are closed (energizing the coil). A 3.0 ohm coil will tend to run a little cooler at 12 VDC input, since the added primary resistance reduces the amount of electrical current flowing through the primary winding in the coil.
Pertronix wrote:Q. How to correct a low voltage problem?
A. First, if you have an external ballast resistor, connect the red Ignitor™ wire to the ignition wire
prior to the ballast resistor. Second, if you do not have a ballast resistor you must locate a 12
volt source that is controlled by the ignition switch to connect the red Ignitor™ wire to.
As I explained earlier, tapping into the ignition power wire before it passes through the engine compartment multi-connector taps into the full 12 VDC power source that is controlled by the ignition switch, as described above in the Pertronix instructions.

Image
erco wrote:... I plan to run my existing Bosch "big blue" coil, which has a resistance of 3 ohms. Based on what I've read, bypassing the ballast resistor wire is in order.
ImageImage
Product Description
Bosch's 12 Volt 3.4 Ohm blue ignition coil is epoxy filled, which means it won't leak if mounted sideways or upside down like oil-filled units. The coil is compatible with our Computronix and Pertronix Electronic Ignition Modules as well as many other points elimination kits. We almost exclusively use Bosch ignition components in our VWs and recommend only Bosch ignition parts for your VW. The 12 volt coil fits 1967 through 1977 Standard Beetle, 1971 through 1979 Super Beetle, 1967 through 1974 Karmann Ghia, 1967 through 1979 Type 2 Bus models, 1967 through 1973 Type 3 (Notchback, Squareback, Fastback), 1973 through 1974 Thing, and 1980 through 1983 Vanagon models.
Image
The high-output, genuine Bosch "Blue" coil is perfect for most 12 volt 4 and 6 cylinder applications. This model has 3 Ohms internal resistance, so a ballast resistor is not required.

Note: Bosch has changed the look of the venerable "Blue" coil. It's no longer painted blue. It just has a blue label. However, Bosch has assured us that none of the quality or performance specifications have changed.
NOTE: The standard (stock) Corvair DELCO=REMY ignition coil has an internal primary winding resistance specification of 1.28 - 1.42 ohms. The stock Corvair wiring harness includes a resistor wire rated at 1.8 ohms. The two in series (1.28 or 1.42 + 1.8) = 3.08 - 3.22 ohms (Nominal 3 ohm primary resistance). Since the Bosch coil already has all of the needed primary resistance INSIDE THE COIL, the external ballast wire should be bypassed. Leaving the external wire in the circuit will power the Bosch coil via a total input resistance of (1.8 + 3.4) = 5.2 ohms, which will significantly reduce the secondary voltage output to the spark plugs. To obtain the full spark plug voltage that the Bosch coil was designed to produce, the extra external ballast resistor wire must be bypassed. Doing so will provid both the Bosch coil and the Pertronix Ignitor electronic module with the correct nominal 12 VDC they were designed for.

It is not a bad idea to relocate the coil mount position. The standard installation of the ignition coil was always mounting it directly on the right cylinder head. The cylinder head on an air cooled engine gets very hot, and a significant portion of that heat can be transferred via the coil mounting bracket to the coil body itself. I would recommend relocating any coil as shown in the pictures below.

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Brad Bodie
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Image 1966 Corvair Corsa Convertible

erco
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Re: Ballast Resistor Wire

Post by erco »

I just saw that my hero azdave answered this very question about a week ago at viewtopic.php?f=55&t=16384
azdave wrote:
Tue Aug 25, 2020 5:53 am
Your resistor wire is wrapped in woven cloth and starts at the large rectangular plug in the top left engine compartment. It runs along inside the harness heading to the coil but then folds back upon itself inside the wrapping and heads back to the 2-pin plug for the the starter solenoid. Power to the coil bypasses the resistor wire while the starter is engaged so that the coil will temporarily see a full 12V for cold winter starts. After the starter turns off, the power to the coil again loops through the resistor wire circuit before reaching the coil.

erco
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Re: Ballast Resistor Wire

Post by erco »

This Bosch listing says the ballast resistor must be left in place with Pertonix.

Somebody's wrong.

https://vwparts.aircooled.net/12V-Bosch ... -012us.htm

plrgpr
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Re: Ballast Resistor Wire

Post by plrgpr »

OK, I’m still a bit confused, but here is what I believe y’all are saying. My car has the red wire going directly to the positive side of the coil from the distributor. As I understand, all that’s said here, is that this incorrect. The red wire should be spliced into the 20 B/P wire prior to the main pin connector going to the engine compartment. And I need to replace the 1 1/2 ohm Pertronix coil with the OEM coil. BTW, the car runs & starts perfectly, however, as I stated earlier in this post, I have recently burned up the distributor rotor, which has never happened to me me in my 55 yrs. of driving and owning cars.
Gary Roberson
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Re: Ballast Resistor Wire

Post by 66vairguy »

erco wrote:
Thu Sep 03, 2020 9:25 pm
This Bosch listing says the ballast resistor must be left in place with Pertonix.

Somebody's wrong.

https://vwparts.aircooled.net/12V-Bosch ... -012us.htm
Wow - this is the typical confusion around Pertronix installations.

The Bosch "Big Blue" gets a lot of hype, but it's just a good coil and no better than a good stock Corvair coil. It's also the wrong primary resistance.

The TOTAL (ballast wire and coil) resistance for the Corvair (and most Chevies) in the mid 60's was about 3.2 Ohms. As Azdave pointed out the ballast wire is by-passed during starting for a higher coil output voltage to compensate for lower batter voltage when the starter is engaged (battery voltage can drop to less than 10VDC during starting in freezing temperatures). It was a clever design. The stock points OR the Pertronics Ignitor (not Ignitor II) require a minimum of 3.0 Ohms for reliability. So yes you can run the a 3.0 ohm coil with the ballast by-passed, but you loose the "higher coil voltage function during starting (Why would you want too?).

As for the "Flamethrower" coils - based on my experience I would not use them. If you need a good coil buy a quality after market coil for a 1965 Chevrolet SBC (283,327 c.i. V8). It is as close as you can get to a Corvair Delco 140HP coil and works fine.

Basically you want a stock points setup that is correct, then JUST replace the points with the Ignitor 1162A and set the timing. Easy and the MOST reliable Pertronix installation. I will not use the Ignitor II and "hot" Flamethrower coil as there will be NO improvement in engine performance despite the advertised hype.

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Re: Ballast Resistor Wire

Post by 66vairguy »

plrgpr wrote:
Thu Sep 03, 2020 1:02 pm
66vairguy, see photos. My car definitely hast the electronic ignition installed. This is apparently what I have installed on my 66 140 4-sp. I say apparently as I’ve had the car for only 1 1/2 yrs and these boxes, with the OEM parts inside came with an assortment of parts along with the car. Brad indicated that I should have the 3 ohm coil, but appears I have the 1 1/2 ohm. Two wires from the distributor, red one is on the positive side. I say all this to say that the distributor rotor failed and left me stranded a few weeks ago cruising down the road at 60 mph! The inside of the cap was coated with goldish colored filings (same color as the end of the rotor) and the end of the metal contact on the rotor burned off which, I assume, ultimately caused the engine to quit. I have no idea how many miles were on the rotor, I’ve put a couple of thousand on the car since I’ve had it. Do you think that the electronic conversion had anything to do with the rotor failure? Do I have the proper system installed on my car?
Your Pertronix Ignitor 1162A (often called the Ignitor I) is the unit I use. This requires a minimum ballast AND coil total resistance of 3.0 ohms (Corvair ballast is 1.8 ohms plus stock Delco coil is about 1.3 ohms for a total of 3.1 ohms). So NO a 3 ohm Flamethrower is incorrect to use with with the Corvair ballast in place. You 1.5 ohm Flamethrower WITH the stock ballast is correct (however per my experience I would not use any Flamethrower coil, but if yours works then no need to change it). If your Flamethrower coil fails I'd use a QUALITY replacement coil for a 1965 Chevy SBC (283,327 c.i. V8). As close as you get to the 140HP coil now.

Many connect the Ignitor RED wire to the coil "+" terminal. It's not the best power source, but it seems to work. I connect the Ignitor RED wire to the ignition switched voltage BEFORE the ballast wire at the engine bulkhead connector. If you are not skilled at working with wiring, and the car runs fine then leave the Ignitor RED wire on the coil "+" terminal.

The brass filings in the cap indicate a clearance problem. I have found replacement rotors that fit too tight and would sit up too high hitting the distributor cap terminals. Also I've seen distributor caps on crooked, specifically if not notched for the Pertronix wires, that will cause contact/rotor interference. BTW the Ignitor magnet ring that fits below the rotor on the points cam is NOTORIOUS for being too tight and won't go down all the way (makes the rotor sit too high) or if forced it will eventually crack. A small machinist file to carefully remove casting flash plastic will fix it. DON'T make it too loose!

Good luck.

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Re: Ballast Resistor Wire

Post by bbodie52 »

12V Bosch Blue Coil with Mounting Bracket, US Version, 00-012US is a factory replacement Bosch Blue Coil with the 3 ohm impedance (internal resistance), compatible with points, and points replacement devices, in 12V electrical systems. There are 5 DIFFERENT "Bosch Blue Coils" last we checked, only ONE is correct for you (This one). If you are running points, or a a points replacement device (Compufire or Pertronix), you MUST make sure your ignition coil has the ballast resistor. Stock Bosch blue coils have the 3 ohm ballast resistor INSIDE the coil. If your coil or primary ignition winding doesn't have this ballast, the distributor will BURN UP and leave you walking. This coil comes WITH the mounting bracket too!
There statement (above) is somewhat confusing.

The primary purpose of the external ballast resistor (or resistor wire) was to serve as a current limiting device that adds approximately 1.5 ohms (1.8 ohms in the Corvair wiring harness, according to the shop manual specifications) to the TOTAL PRIMARY CIRCUIT RESISTANCE. The Delco-Remy coil primary resistance specification (according to the Corvair Shop Manual) is 1.28-1.42 ohms. So two resistances in series add up to a primary resistance between 3.08 and 3.22 ohms. With a Bosch Blue Coil (3 ohm primary resistance) or a Pertronix Flame-Thrower coil (3 ohm version), the internal coil primary resistance provides all of the current limiting needed to preserve the contacts on ignition points to make them last longer. Without the extra resistance (if the coil internal resistance is 1.5 ohms or less) and if there is no added external ballast resistor in the circuit, the total current flowing across the ignition points contacts will increase the arcing and burning that occurs each time the switch (points) opens and closes. The GM engineers added the resistor wire to the wiring harness to make the points last longer in normal operation by lowering the voltage from a nominal 12 VDC battery voltage to approximately 7 VDC. The lower voltage reduces the current flow (measured in amps) between the ignition points contacts, so they last longer between adjustments or tune-ups. This lower current flow across the points and through the coil primary winding also reduces heat buildup, which helps to prolong the life of the coil. However, reducing the input voltage using a ballast resistor also weakens the spark voltage output from the coil secondary winding to the spark plugs. GM engineers felt that te weaker spark voltage was acceptable for normal engine operation, but they felt the cold engine needed a little help while being cranked at a slow speed by the starter to get things running. They created a bypass of the external ballast resistor that occurs only when the starter solenoid is engaged to crank the engine. When the solenoid is engaged to turn on the starter motor and crank the engine, it also feeds a full 12 VDC battery voltage to the ignition coil to temporarily boost the coil output to the spark plugs. This helps to ignite the fuel/air mixture in the combustion chambers to get the engine started. Once the engine starts, the driver releases the key, which shuts the starter off, disengages the starter solenoid, and shuts off the boost voltage to the coil (letting it revert back to the lower voltage being provided by the ballast resistor wire circuit). The ignition points only have to tolerate the higher current flow produced by 12 VDC for the duration that the engine is being cranked. Once the engine is running, the points happily conduct their ON/OFF operation with only about 7 VDC feeding the coil.

Some coils have an internal primary resistance of 3.0 ohms, but most use the factory standard of 1.5 ohms. The super high-output racing coils may only have 0.6 ohms or less primary resistance to boost their spark voltage even higher. This is needed in engines that rev at very high racing speeds, and that often have very high compression ratios or superchargers/turbochargers that boost combustion chamber pressures to levels that make it difficult to ignite the fuel/air mixture. Ultra high output coils and distributor modifications to allow the distributor to operate those racing coils are needed for racing applications — an environment that the air cooled Corvair engine never sees. Because of the air cooled engine design limitations, racing Corvair engines run at lower RPM settings and with lower compression ratios, and if supercharged/turbocharged they generally run with lower boost pressures than the water cooled V-8 racing engines see. So the ultra high output racing coils are not needed for the normally aspirated Corvair engine (although some turbocharged engines may benefit from a higher spark voltage under full boost, because of the higher combustion chamber pressures encountered under full boost).

The Corvair engine benefits from electronic distributors because they eliminate the ignition points. This produces more reliable, more stable operation. The ON/OFF switching of the ignition points is now done by an electronic transistor, using magnetic or optical trigger devices to control the transistor switching action. The transistors can handle the higher current produced by 12 VDC operation of the coil (1.5 ohm or 3.0 ohm), but only some breakerless systems can handle the very high current levels seen with an ignition coil that uses a 0.6 ohm primary! The Pertronix Ignitor II and the Stinger electronic distributor can handle that type of high energy coil. The Pertronix Ignitor I or the Crane Cams/FAST XR700 cannot handle those high energy coils, because their switching transistors are not capable of handling so much primary current.

Using a 3.0 ohm performance coil like the Bosch Blue Coil or the Pertronix Flame-Thrower P/N: 40511 (3.0 Ohm) helps the coil to run cool on a full 12 VDC primary input when connected to a six cylinder engine. Relocating the coil away from the hot Corvair cylinder head also helps. Also, turning the key OFF when the engine is not running ensures that the coil is not continuously conducting electrical current with the engine not running. That also can damage a coil by causing it to overheat.

QUESTIONS? :dontknow:
Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible

erco
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Re: Ballast Resistor Wire

Post by erco »

A perfectly lucid and well-articulated answer, Brad. Thank you for crafting such a deliciously detailed technical reply.

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Re: Ballast Resistor Wire

Post by erco »

Pertronix sells a $3 lighting relay for $35, pretty good markup! https://pertronixbrands.com/products/pe ... 7256224804 Install instrux at https://cdn.shopify.com/s/files/1/0247/ ... s/2001.pdf

A relay is a good solution for getting a full 12V to the Ignitor module, but I'd use a smaller 5V relay, low current coil and contacts sized to the current requirements of the Ignitor module (pretty low I'll bet). Drive both the relay and the ignition coil through the ballast resistor (5V relay may need another series resistor to limit current) and use the relay to switch the Ignitor directly to battery +12V.


WRT concerns about 1.5 vs 3 ohm coil resistance in a stock system, it may be a moot point. "Up to 8 amps" flow through points and coil, according to https://www.liveabout.com/point-type-ig ... ay%20speed
There are over 20 feet of 50+ year-old wiring in the car, running from the battery up to the ignition switch and back to the coil. I'm sure there are several extra random ohms in the switch and various ancient oxidized electrical connectors. A relay could eliminate these variables and provide potentially better performance. I might consider adding an external ballast resistor, wired through a larger relay to bring +12V to the coil to eliminate these effects.

erco
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Re: Ballast Resistor Wire

Post by erco »

Just received this email reply from Pertronix after asking which Flamethrower coil to use:

You need to use the 3.0 ohms coil when not using a ballast resistor.

Your Pertronix Team,
Marvin Grebow Jr.
Technical Dept.


Interesting that Amazon sells the #40011, 1.5-ohm coil for ~$35: https://www.amazon.com/PerTronix-40011- ... B00199F2WW

and the #40611, 3-ohm coil for $48: https://www.amazon.com/pertronix-40611- ... B000N2XOYE

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