1963 Turbo ( stock) Spark Plugs

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66vairguy
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Re: 1963 Turbo ( stock) Spark Plugs

Post by 66vairguy »

Your story seems familiar - I run into so many incorrectly configured Petronix installations.

The Petronix Ignitor (I) will malfunction if you don't have a minumum of 3 ohms of input resistance at the coil - this is the same input impedance regular points require. The stock Corvair turbo system used a different coil, but also used a ballast. I don't recall if the 63 used the ceramic ballast resistor or the wire.

You said you DID NOT use the ballast resistor so your Flamethrower coil would have to be the 3 ohm version to work with the Ignitor I, you never posted a part number so hard to say what you had.

Clark's does not give a part number for the Crane Fireball coil and no specifications (sigh). The pictures indicates a PS20 and the spec. says it comes with a "resistor for points use" and Clark's online description says "DO NOT NEED TO USE THE RESISTOR INCLUDED". So the coil impedance is designed for use with the Corvair ignition ballast. The Crane PS20 primary resistance is 1.4 ohms and that is too low to work with the Petronix Ignitor I (minimum 3.0ohms) without the ballast. The Crane PS20 WILL work with the Petronix Ignitor II designed for low impedance (down to 0.5 ohms) with NO ballast and it will have a spark with greater energy (needed for a turbo during boost).

If indeed you do not have a ballast resistance with the coil your Petronix Ignitor I won't last. You might go back and do some measurements with an ohm meter (or find someone with ignition experience to help).

The Petronix Ignitor I with a stock coil and ballast resistor is more than adequate for a NON turbo car. In your case I would stay with the PS20 coil run directly off 12VDC (no ballast) and use the Petronix Ignitor II for the best ignition spark performance during boost. The only down side with the Ignitor II is it looses timing reference under about 700RPM (no go for automatics), but typically a turbo engine idles around 900 RPM.

Let us know what you find.
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Grandpacorvair
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Re: 1963 Turbo ( stock) Spark Plugs

Post by Grandpacorvair »

So,now I'm confused... likely my lack of knowledge.. This paragraph says:

"The Crane PS20 primary resistance is 1.4 ohms and that is too low to work with the Petronix Ignitor I (minimum 3.0ohms) without the ballast. The Crane PS20 WILL work with the Petronix Ignitor II designed for low impedance (down to 0.5 ohms) with NO ballast and it will have a spark with greater energy (needed for a turbo during boost)." and "If indeed you do not have a ballast resistance with the coil your Petronix Ignitor I won't last. You might go back and do some measurements with an ohm meter (or find someone with ignition experience to help). "

That seems to imply that the PS20 (what I am running) shouldn't be used with the Pertronix I WITHOUT the ballast resistor. My car has the 64 harness in the engine compartment but I don't think it has the resistance wire within the harness for the coil. Not sure how to verify that though......I measured pretty close to 12 volts at the coil IF memory serves. I'll recheck that...

To further complicate things, Clark's chart shows that the PS20, #4 on the chart, is compatible with the Pertronix I ONLY and not the Pertronix II.... (see attachment). More confusion comes in in that Clark's says no resistor is needed... Does that statement mean that Clark's is assuming that some form of ballast exists within the car already and that no 'new' or additional resistor is required, or that NO form of ballast is needed....ugh.


FWIW, the Fireball coil that failed within weeks was the 3.0 ohm version. My current configuration is the Crane PS20, no obvious ballast resistor and possibly no resistance wire within the harness, and I am running a newer Pertronix I.

I considered the Pertronix II but read several comments about reliability and use of it with Corvairs being problematic because of heat issues from the Corvair engine.

Have I been able to state my confusion or simply muddied the waters even further? ;)

In any case i appreciate your taking time to respond and offer help.
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coil.jpg
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Kerry Borgne
1963 Spyder Convertible
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bbodie52
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Re: 1963 Turbo ( stock) Spark Plugs

Post by bbodie52 »

Image

Image
According to the attached Ignitor I instruction sheet, the Ignitor I is compatible with "points style" coils. The resistor wire in the Corvair wiring harness is 1.8 ohms. The Delco-Remy ignition coil primary resistance specification is 1.28-1.42 ohms. This means that the total primary resistance in the circuit connected to the ignition points would be the sum of the resistor wire plus the coil primary resistance: 3.08-3.22 ohms. You indicated earlier that the Crane PS20 primary resistance is 1.4 ohms. With the standard Corvair ballast resistor wire, the total primary resistance would be 3.2 ohms, which would satisfy the Pertronix Ignitor I specification for an expected load for "points style" coils. Ignition points are not expected to operate switching current with a full 12 V DC feed. The Ohms Law formula for current (I) is I=V/R. (Current = Voltage / Resistance). With no external ballast resistor, the current carried by the points with a Crane PS 20 coil alone would be approximately 8.57 amps (8.57 = 12/1.4). If the ballast resistor wire is present in the circuit (1.8 ohms) the current across the points would be reduced to approximately 3.75 amps (3.75 = 12/3.2), which is less than half of the current without the ballast resistor. You can see why the points would quickly be destroyed of only a Pertronix Flamethrower II coil were in the circuit, with no external ballast resistor: 20 Amps! (20 = 12/0.6). As shown below, the Pertronix Ignitor II is designed to be compatible with a Flamethrower II coil (0.6 ohms), and that coil is designed to produce an ultra high secondary output voltage of 45,000 volts, so it requires a full 12 V DC input at the primary and 20 amps passing through the circuit to ground (switched by a Pertronix Ignitor II only!)

The Ignitor I expects to see current that is comparable to what points work with (less than 4 amps, based on a nominal 3 ohm primary resistance). That 3 ohm primary resistance can be provided by a 3.0 ohm coil by itself, or by the cumulative primary circuit resistance of 1.8 ohms from the external ballast resistor wire plus the internal coil resistance of 1.28-1.42 ohms (3.08-3.22 ohms). The Pertronix Flamethrower I coil is available in 1.5 or 3.0 Ohm primary resistance values to accommodate points or a Pertronix Ignitor I that will be installed in a car with, or without an external ballast resistor. If your car does not have an external ballast resistor or resistor wire, you would buy a coil with a 3.0 ohm primary internal resistance. Otherwise, you can combine a nominal 1.5 ohm coil with an external ballast resistor in the primary circuit like the one shown below...

Image
:link: http://www.jegs.com/i/JEGS/555/40102/10 ... oCEy3w_wcB
  • 1.6 Ohm
  • Installed on the battery wire to the coil (+).
  • For use with coils that do not utilize a built-in resistor such as JEGS 555-40100 or 555-40105 coils.
  • Should always be mounted to the firewall (or another non-heated metal surface) for additional heat dissipation.
The chart in the Clark's Corvair Parts catalog is somewhat misleading. The Pertronix Ignitor II will tolerate any coil, as long as the total primary resistance is 0.6 ohms or greater. According to the attached Pertronix instruction sheet, the Ignitor II is compatible with coils having a resistance of 0.6 ohms or greater. This means it is compatible with standard OEM coils and aftermarket high performance coils, including ultra high output coils like the FlameThrower II that only has an internal primary resistance of 0.6 ohms. A higher coil resistance will not hurt it. The Ignitor II red wire should be attached to a 12 V DC power source (no external resistor wire or ballast resistor in this power circuit. The Ignitor electronics requires a full 12 V DC).

If there is no resistance wire in the Corvair wiring harness (can be measured in ohms using a multimeter) you need to add an external ballast resistor to the circuit to provide your Pertronix Ignitor I with a proper current-limited circuit when connected to the coil negative terminal (black wire). The red wire must be provided with a full 12 V DC, by tapping into the primary ignition circuit BEFORE the external ballast resistor, as shown below...

Left-click the image below to enlarge for better viewing...
Pertronix Ignitor Module Wiring Diagram.jpg
Attachments
Pertronix Ignitor 12v neg Instructions.pdf
Pertronix Ignitor 12v neg Instructions
(73.1 KiB) Downloaded 20 times
Pertronix 91162A Ignitor II Instructions.pdf
Pertronix 91162A Ignitor II Instructions
(1.01 MiB) Downloaded 20 times
Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible
66vairguy
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Re: 1963 Turbo ( stock) Spark Plugs

Post by 66vairguy »

OH - you have a 64 wiring harness!! Well that explains a lot. If I recall correctly (folks feel free to correct me). The 64 Spyder wiring harness eliminated the earlier ceramic ballast (special on the earlier Spyder Turbo cars) and went with ballast resistance wire in the harness like the Monza.

WITH the ballast wire the Flamethrower coil at 3ohms would produce a weak/inferior spark at the plugs. BTW - This is a COMMON error I see a lot as Petronix listed that coil for GM six cylinder applications and the Corvair uses a coil very similar to the V8 coil - about 1.35ohms. So your new 1.40ohm coil is a good choice.

About the ballast ----- I've posted this before, but here goes ---- You will ALWAYS see about 12VDC at the coil "+" unless the points (or electronic) switch are closed. When the points close (or electronic switch) the voltage drops across the ballast so you see about 6VDC at the coil "+" terminal.
When the engine runs the voltage will vary between 14 - 6VDC (square wave) so a meter on DC is not going to give a valid reading with the engine running. These numbers vary since the system voltage can vary from 12.3 to 14.8VDC depending on battery condition and if the car is running (charging).

Here is a simple way to test for a ballast --- disconnect the distributor wire from the coil "-" terminal. Connect volt meter positive to coil "+" terminal and the meter negative to ground. Turn on the key (don't engage starter) and you should see about 12VDC. Use a wire (at least 18 gauge) and ground BRIEFLY the coil "-" terminal and the volt meter should drop to 5-6VDC to indicate a ballast resistor voltage drop during amperage flow through the coil.
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Grandpacorvair
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Re: 1963 Turbo ( stock) Spark Plugs

Post by Grandpacorvair »

I think I'm getting a headache heheh..

Ok. I did as you suggested. Unloaded the voltage reads 12.33, grounding the negative side of the coil returns a voltage of 9.89. IF I did the math right that gives a current draw of 6.5 amps. Pertronix suggests a current no higher than 4 amps for a six cylinder engine.. :(

As I mentioned this car has a 64 engine harness. It was purchased from Clarks. I was able to locate the resistance wire by following your directions, however as is often the case with our Corvairs, there is a difference, the wire is NOT cloth covered. It is a fairly heavy pinkish wire that connects as indicated. Is it a resistance wire? Hard to say, measuring resistances that small are problematic, even on my digital meter.

Incidentally, I heard back from Pertronix support and they suggested a 2 ohm resistor assuming there is no resistance wire present. I also emailed Clarks for a clarification of their "no resistor needed" suggestion in the catalog, but haven't heard back yet.

Clarks doesn't seem to list the resistance for purchase.
Kerry Borgne
1963 Spyder Convertible
Birmingham, Michigan
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bbodie52
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Re: 1963 Turbo ( stock) Spark Plugs

Post by bbodie52 »

With an input source voltage of 12.33 V DC, an output voltage of 9.89 V DC, and assuming your Crane coil is contributing 1.4 ohms to the voltage divider circuit, that leaves only 0.345 ohms resistance from the external circuit wire. If you were to add the external ballast resistor (1.6 ohms) you would have the desired 3.0 ohms total primary resistance, producing a current of approximately 4.1 amps and an output voltage of about 5.754 V DC measured at the grounded coil negative terminal.

It appears that there is no resistor wire in the circuit. Recommend adding the 1.6 ohm ballast resistor previously mentioned. That should keep your Pertronix I happy. Just be sure you have provided full battery voltage to the red Pertronix wire.

Clark's does list the ballast resistor. Search for "ignition" and you will find it listed on page 75A — somewhat pricey, though and no resistance value given.

Part number C3825: 62-63 TURBO COIL RESISTOR

Weight: 0 lbs 6 oz
Catalog Pages(s): 75A,OT,47
Price: $ 21.15

Recommend the 1.6 ohm ceramic resistor from the source I listed earlier, Amazon.com, a local auto parts store, etc. I believe that the Crane Cams coil is shipped with a ceramic resistor in the box with the coil, if it hasn't been misplaced.

1964 Ignition Wiring Diagram
1964 Ignition Wiring Diagram

Image
Voltage Divider Calculator
:link: http://www.ohmslawcalculator.com/voltag ... calculator

Voltage Source (VS) 12.33 Volts (V) [Battery]

Resistance 1 (R1) 1.6 Ohms [Ceramic Ballast Resistor]

Resistance 2 (R2) 1.4 Ohms [Crane Cams PS20 Ignition Coil]

Output Voltage (VOUT) 5.754 Volts (V)

Image
Image
Brad Bodie
Lake Chatuge, North Carolina
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66vairguy
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Re: 1963 Turbo ( stock) Spark Plugs

Post by 66vairguy »

I have to admit I'm not a 64 expert. I do know the Monza harness used a 1.8ohm resistance wire. As you said it's difficult to verify with a standard meter due to poor resolution. Figure if the wire were 1.8 ohm and the coil 1.4 ohm the voltage drop through the wire from 12.33 would be about 6.94VDC so the coil "+" terminal should be 12.33 - 6.94 = 5.39VDC and that's about right for 12.33 (when the engine runs the system 14.5VDC would give 6.3 at the coil "+" terminal). Your measurements indicate a very low resistance, about what you'd see due to just connections.

The Clark's M&H harness's I've seen do use the cloth covered wire. It's possible the 64 turbo harness used a different resistance wire, BUT I've seen nothing to indicate that - then again the EM wiring schematics for the turbo cars are lacking.

At this point I'm going to suggest you get a Corvair expert on electrics to look at your car. Diagnosing via the forum is difficult. Other issues could be at play like the starter ballast by-pass switch wiring, or previous wiring repairs!!

Clark's does sell the ceramic resistor, not sure if it's a 1.8ohm, which would be a good fit with your coil - IF needed. I have some old parts stores numbers for a 1.8 ohm that may still be valid - PM me if you need them.
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Re: 1963 Turbo ( stock) Spark Plugs

Post by bbodie52 »

:idea: There is another possible way to determine if there is a resistor wire present and if it is making any difference in the voltage seen at the negative coil terminal. Simply disconnect the wire on the coil positive terminal. Then run a temporary jumper wire between the battery positive terminal and the coil positive terminal. This would be a simulation of the primary circuit with the key on and no resistor wire present. If you read the same voltage at the coil negative terminal with the circuit grounded (points closed) — approximately 9.89 V DC — you have in-effect confirmed the lack of a resistor wire with a simulation by using a piece of wire to connect the battery to the coil positive terminal. If the voltage reads as it did before then you can assume that there is no ballast resistor wire present in your engine wiring harness. The voltage fed to the coil positive terminal would be the same as the voltage fed there with the starter solenoid engaged (which is intended to bypass the resistor wire for starting purposes).

If you successfully run the simulation and confirm the lack of a ballast resistor wire in the circuit, you can add the suggested 1.6 ohm external ballast resistor by mounting it to the perimeter frame near the coil. Then connect the primary lead to the new ballast resistor and connect the output of the ballast resistor to the coil positive terminal. The cumulative total of the ballast resistor (1.6 ohm) and the Crane PS20 ignition coil (1.4 ohm) will give you the desired 3.0 ohm primary resistance that is needed for the Pertronix Igniter I ignition module.
Brad Bodie
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Grandpacorvair
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Re: 1963 Turbo ( stock) Spark Plugs

Post by Grandpacorvair »

Hmm that's an option. However there may be a fly in the ointment. There is the wiring between the battery source to the ignition switch and back to the coil to consider? When we're taking about small changes in resistance it all adds up. I think ;) Connecting the coil directly to the battery removes all that too...(my headache is coming back) I think I need to measure the voltage, under load, at both ends of the 'resistor wire'. I betting that I am going see very close to the 9.89 vdc at both ends and that the voltage drop is do to aging connections upstream, most likely the 50 plus year old ignition switch.

Which brings me to another question. To maintain the original intent of the engineers, shouldn't the resistor be inserted where the resistor wire was, circuit wise? That way the coil will still see the full 12vdc during cranking? (putting aside for the moment IF it really needs the extra voltage starting a cold engine in the summer..)
Kerry Borgne
1963 Spyder Convertible
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Grandpacorvair
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Re: 1963 Turbo ( stock) Spark Plugs

Post by Grandpacorvair »

Oh, also heard from Clarks, the resistor is required if there is no resistance wire used. Pretty much the conclusion we've arrived at.

I wonder if anyone has an old harness with the resistance wire intact...

Yes, I am that anal! lol!
Kerry Borgne
1963 Spyder Convertible
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Re: 1963 Turbo ( stock) Spark Plugs

Post by 66vairguy »

Brad suggestion won't work, unless I missed something. Hooking batter voltage to the coil "+" and grounding the coil "-" will simply show a 12.33 drop across the coil - one load. (if the wire gauge is too small you might get some voltage drop in the wire).

An experienced electrical person would install a dummy load of about 1.8 ohms (100 WATT) and measure the voltage drop for both the harness and coil separately.

You said you had a 64 harness, but you have a 63 Turbo. Are you sure this isn't a 62-63 Spyder wiring harness (it used the ceramic ballast). Also the coil you got from Clark's is suppose to come with and external ballast resistor that isn't used if you have a ballast. If you have that ballast you could install it temporarily and check the voltages. NOTE THE CERAMIC BALLAST LOADS GET HOT!!

Again I suggest finding an electrical person to help as we are making assumptions here - and I learned decades ago you have to go verify before you start throwing parts at a problem. I run into so many "creative" wiring fixes that explain problems.
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Re: 1963 Turbo ( stock) Spark Plugs

Post by bbodie52 »

We keep running around in circles. The standard Crane Cams PS20 coil is already contributing 1.4 ohms of internal primary resistance. Pertronix sells their Flamethrower coil in both 1.5 and 3.0 ohm versions to accommodate vehicles that lack external ballast resistors or resistor wires in the primary circuit. So far all the evidence presented would seem to indicate a lack of a 1.8 ohm resistor wire in the replacement engine compartment harness that has been installed. (Perhaps Clark's could confirm this?) If the Crane Cams PS20 coil is the only source of primary circuit ballast resistance (1.4 ohms) that would explain your previous measurement of 9.89 volts at the grounded negative terminal (with current flowing). The presence of an external 1.8 ohm ballast wire (if it existed) would have reduced the measured voltage to about 6-7 volts, instead of the 9.89 volts measured.

An added ceramic ballast resistor does not need to be physically positioned where the resistor wire would sit. When they were installed in 1962-63 Spyders the ceramic ballast resistor was actually mounted on the perimeter frame, near the distributor and coil. To duplicate the starter solenoid resistor bypass, a connection would be wired directly to the coil positive terminal from the yellow wire that comes from the solenoid (provides a full 12 V DC when cranking the engine). Another connection would be made from the ignition switch primary wire (from the multi-connector). to the ceramic resistor and then from the ceramic resistor to the coil positive terminal. This would apply ballast resistor reduced voltage when the key is ON, and an override 12 V DC from the starter solenoid when the starter is engaged. (Mounting the ceramic resistor on the engine compartment perimeter frame helps to conduct heat away from the ceramic resistor).
Brad Bodie
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Grandpacorvair
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Re: 1963 Turbo ( stock) Spark Plugs

Post by Grandpacorvair »

Bypassing the math for a minute ;)

Here is a picure of what may be the resistance wire. It connects in the proper places based on the diagrams that were posted above. Still haven't been able to prove (or disprove) if it IS resistance wire but I'm working on that. Easiest solution is to remove it and use the 1.6 ohm resistor and that may be what I will do in the end.
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coil wire.jpg
Kerry Borgne
1963 Spyder Convertible
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Grandpacorvair
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Re: 1963 Turbo ( stock) Spark Plugs

Post by Grandpacorvair »

Ok, spent some more time with this, this morning. Using the Jegs resistor (1.6ohm) as a reference resistance, I measured directly across the pink wire pictured above. the wire measures 0 ohms. I also measured across the wire while under load from the coil (- lead shorted to ground) and got NO voltage drop across it and both ends gave the same voltage when referenced to ground. It MAY have been a resistor wire at one time but it sure doesn't seem to be one now. From what I can see it doesn't look to have been molested at all.

Without an actual piece of resistance wire to test, I can't go any further. Obviously, as I mentioned above, the answer is to install the Jegs 1.6 ohm ceramic resistor and eliminate any guess work.

Incidentally, I measure 9.8 vdc at the wire, right at the big connector.(under the same test conditions.) That suggests that somewhere within the car body I'm loosing close to 3 volts. I guess the next place to check is the ignition switch? What do you think? Is that normal or should I pursue this?
Kerry Borgne
1963 Spyder Convertible
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Re: 1963 Turbo ( stock) Spark Plugs

Post by bbodie52 »

wrote:Sat May 27, 2017 1:50 am

We keep running around in circles. The standard Crane Cams PS20 coil is already contributing 1.4 ohms of internal primary resistance...
Grandpacorvair wrote:Thu Jun 01, 2017 8:29 am

...I measured directly across the pink wire pictured above. the wire measures 0 ohms...

...Incidentally, I measure 9.8 vdc at the wire, right at the big connector.(under the same test conditions.) That suggests that somewhere within the car body I'm loosing close to 3 volts...
bbodie52 wrote:Fri May 26, 2017 7:42 pm

:idea: There is another possible way to determine if there is a resistor wire present and if it is making any difference in the voltage seen at the negative coil terminal. Simply disconnect the wire on the coil positive terminal. Then run a temporary jumper wire between the battery positive terminal and the coil positive terminal. This would be a simulation of the primary circuit with the key on and no resistor wire present. If you read the same voltage at the coil negative terminal with the circuit grounded (points closed) — approximately 9.89 V DC — you have in-effect confirmed the lack of a resistor wire with a simulation by using a piece of wire to connect the battery to the coil positive terminal. If the voltage reads as it did before then you can assume that there is no ballast resistor wire present in your engine wiring harness. The voltage fed to the coil positive terminal would be the same as the voltage fed there with the starter solenoid engaged (which is intended to bypass the resistor wire for starting purposes).
Your last post indicated that you measured 0 ohms across a wire that you were not sure was a resistor wire. When you measured 0 ohms through that wire you proved that is just a wire! It is NOT a resistor wire! You further proved this when you measured (again) 9.8 V DC in the circuit, but you seem confused as to why you are losing 3 V DC somewhere… that somewhere is the internal primary resistance (1.4 ohms) that is already built in to your Crane Cams PS20 ignition coil. Your direct measurements of the wire resistance (0 ohms) and the lack of a voltage drop because of it just being a straight wire and not a resistor wire, and the built in voltage drop that is a function of the primary winding in the ignition coil accounts for the voltage drop in the circuit that you already measured. If you add an external ballast resistor (1.6 ohms) you will reach the desired total primary resistance of 3 ohms, which will result in the desired voltage drop to a nominal 6-7 V DC (calculated 5.754 V DC). If the wire in your photograph was actually a resistor wire, you would have already attained that voltage reading when you grounded the negative terminal of your ignition coil. But without an external ballast resistor (wire or ceramic resistor) the voltage drop is not enough to satisfy the Pertronix electronic module.

Image

Figure 3 above (from the Pertronix instruction sheet) shows the correct way to wire in the external 1.6 ohm ballast resistor, to power the coil through the resistor while powering the Pertronix electronic module with a full 12 V DC battery voltage to the RED Pertronix module power wire. (Figure 2 above would only be appropriate if you had purchased a Pertronix Flame-Thrower 3.0 ohm ignition coil (1.5 or 3.0 Ohm primary resistance values available) instead of the Crane Cams PS20 1.4 ohm ignition coil).
Brad Bodie
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Grandpacorvair
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Re: 1963 Turbo ( stock) Spark Plugs

Post by Grandpacorvair »

Thanks Brad , for all your help. I'll update this 'discussion' when I dig into it a little further. For now I'm simply going to install the resistor and ignore the "need" for the additional starting voltage provided to the coil from the solenoid during 'cranking'. If the voltages and current work out I'm all set. Later on, I'll probably add the additional wire..maybe ;)
Kerry Borgne
1963 Spyder Convertible
Birmingham, Michigan
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