Glenn's question moved from another thread....
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Hi All,
I've had MSD on my car for 4 years, previous owner installed it two years before I bought it. I've Had no problems. I only drive the Pantera a couple of times a month so that may be the reason it has lasted.
Now the real reason for my post...
1 What is required to switch from MSD to Duraspark?
2 What signals the tach?
Glenn
I've had MSD on my car for 4 years, previous owner installed it two years before I bought it. I've Had no problems. I only drive the Pantera a couple of times a month so that may be the reason it has lasted.
Now the real reason for my post...
1 What is required to switch from MSD to Duraspark?
2 What signals the tach?
Glenn
1)Duraspark distributor, control box (brain) and a harness.
2)The harness will have a terminal on the coil horseshoe that says tach. That is the sensor pickup.
There is a 12v terminal on the back of the tach that will now need to go to a switched source (ignition switch) and there is a ground terminal on the tach. That's it.
2)The harness will have a terminal on the coil horseshoe that says tach. That is the sensor pickup.
There is a 12v terminal on the back of the tach that will now need to go to a switched source (ignition switch) and there is a ground terminal on the tach. That's it.
The only reason the MSD ignition requires a special "add-on box" for the tach is because of the multiple spark feature. The tach can be connected to the coil in the normal manner as long as the ignition does not have multiple sparks, like the DuraSpark modules.
Glenn I can scan & post a schematic of the DuraSpark module wiring this evening if you would like.
DuraSpark modules are identified by the color of the plastic wiring strain relief. The DuraSpark I modules with the red strain relief are a bit more sophisticated than the DuraSpark II versions, they require no ballast resistance in the coil circuit, which is a nice feature for custom installations. Instead of having a ballast resistance to limit current in the coil, the DuraSpark I with red strain relief adjusts current in the coil primary to control current in the secondary and is therefore capable of supplying a "healthier" spark. All DuraSpark modules are designed to sense when the motor is being cranked by the starter motor, and to retard the ignition timing during starting to make the motor easier to crank over. The last nice feature, the DuraSpark modules seem to have about a 20 year or 100,000+ mile life span.
They're a good "street" ignition module. On the other hand, the Ford dizzy is reliable, but not the most wonderful instrument, as it will scatter the ignition timing at around 6000 rpm & above, and the advance mechanism gets "sticky" with age. They are worn out and in need of an overhaul at 50,000 miles or sooner.
One last bit of info regarding Ford ignitions, a paper distributed by Ford in the '70s revealed the performance of the coil decreases with use (mileage). As the coil ages, performance at higher rpm worsens. On a vehicle with a high performance motor, replacement of the coil every couple of years (20,000 miles?) would be a good idea to insure power is not dropping off at high rpm. This information only pertains to Ford coils, aftermarket coils may be better or worse in this aspect.
cowboy from hell
Glenn I can scan & post a schematic of the DuraSpark module wiring this evening if you would like.
DuraSpark modules are identified by the color of the plastic wiring strain relief. The DuraSpark I modules with the red strain relief are a bit more sophisticated than the DuraSpark II versions, they require no ballast resistance in the coil circuit, which is a nice feature for custom installations. Instead of having a ballast resistance to limit current in the coil, the DuraSpark I with red strain relief adjusts current in the coil primary to control current in the secondary and is therefore capable of supplying a "healthier" spark. All DuraSpark modules are designed to sense when the motor is being cranked by the starter motor, and to retard the ignition timing during starting to make the motor easier to crank over. The last nice feature, the DuraSpark modules seem to have about a 20 year or 100,000+ mile life span.
They're a good "street" ignition module. On the other hand, the Ford dizzy is reliable, but not the most wonderful instrument, as it will scatter the ignition timing at around 6000 rpm & above, and the advance mechanism gets "sticky" with age. They are worn out and in need of an overhaul at 50,000 miles or sooner.
One last bit of info regarding Ford ignitions, a paper distributed by Ford in the '70s revealed the performance of the coil decreases with use (mileage). As the coil ages, performance at higher rpm worsens. On a vehicle with a high performance motor, replacement of the coil every couple of years (20,000 miles?) would be a good idea to insure power is not dropping off at high rpm. This information only pertains to Ford coils, aftermarket coils may be better or worse in this aspect.
cowboy from hell
kewl, but one correction, the MSD has a tach output, just have to switch the tach pickup from the coil to the box.
quote:I can scan & post a schematic of the DuraSpark module wiring this evening if you would like.
cowboy from hell
George,
I'd like to see the schematic.
Thanks, Dan
G .... Thanks. I had to copy that one and save it for 6476. I even picked up a Motorcraft Distributor for my Duraspark ignition with a Mechanical Tack drive ... now gotta find a tack for it.
Would you please help me identify my module as Duraspark 1 or 2? It bears Motorcraft P/N D5AE 12A199 A1D. Green strain reliever.
I googled the P/N and it came up as a generic 1975 module. Were there hi-po versions? Would they be a one or a two?
Mine is wired differently than the sketches. My white and red (looks more pink to me) are joined together just after the connector and head off as one red wire. I think it runs (through a sheath) to the + side of the coil. This I'll confirm.
Looking at what the white wire is doing in your sketches, I think my configuration is hurting low voltage spark production. Like when starting. I supposed there was a reason to have two wires.
My distributor P/N is OE O1 D9TE 12127 AKA, brown dot on vacuum advance. Googles as 1979 Bronco with auto trans. Good? Bad? Doesn't matter? I checked with a local engine builder to see if he could curve my distributor to match my cam and other engine parameters. Said he couldn't do electronic distributors and didn't recommend I pursue it. Should I look further while mine is still easy to get out?
Thanks.
I googled the P/N and it came up as a generic 1975 module. Were there hi-po versions? Would they be a one or a two?
Mine is wired differently than the sketches. My white and red (looks more pink to me) are joined together just after the connector and head off as one red wire. I think it runs (through a sheath) to the + side of the coil. This I'll confirm.
Looking at what the white wire is doing in your sketches, I think my configuration is hurting low voltage spark production. Like when starting. I supposed there was a reason to have two wires.
My distributor P/N is OE O1 D9TE 12127 AKA, brown dot on vacuum advance. Googles as 1979 Bronco with auto trans. Good? Bad? Doesn't matter? I checked with a local engine builder to see if he could curve my distributor to match my cam and other engine parameters. Said he couldn't do electronic distributors and didn't recommend I pursue it. Should I look further while mine is still easy to get out?
Thanks.
My notes state " GREEN early solid state ignition (pre 1977) similiar to the Duraspark II , but never popualr for retorfitting, probably because the Duraspark I was superior."
The ideal unit is the RED because of its output.
The ideal unit is the RED because of its output.
Larry to answer your other question the distributor doesn't make a difference. Of course it should be curved for you motor, and any good shop with a dyno normally has a distributor machine. You wouldn't really know what kind of a curve to put into the distributor unless you determine that with a run on the chassis dyno. MOst shops just throw a generic curve into it, a Chevy curve by the way, and they'll tell you to run 12 degrees initial advance.
If the pre-1977 breakerless ignition module has the same functionality as the DuraSpark modules (ignition retard during cranking) then twisting the white & red wires together runs the module constantly in the "spark retard" mode.
You'll find your pre-1977 module has an extra wire not found in the drawings above, a blue wire.
If you are traveling around North America and have a module failure, drop into "Pop's Auto Parts" on Main Street America for a replacement, the module he is most likely to stock is the DuraSpark II module with blue wiring strain relief. This is the most common module, and the module most often employed in breakerless ignition retro-fits. However, as Ron wrote, the DuraSpark I module, with red wiring strain relief, is the superior module. It was only installed in cars destined for the green state (California) where emission standards were stricter. If you price them, you'll find the DuraSpark I module is quite a bit more expensive, which is why Ford didn't use them in more cars.
cowboy from hell
If the pre-1977 breakerless ignition module has the same functionality as the DuraSpark modules (ignition retard during cranking) then twisting the white & red wires together runs the module constantly in the "spark retard" mode.
You'll find your pre-1977 module has an extra wire not found in the drawings above, a blue wire.
If you are traveling around North America and have a module failure, drop into "Pop's Auto Parts" on Main Street America for a replacement, the module he is most likely to stock is the DuraSpark II module with blue wiring strain relief. This is the most common module, and the module most often employed in breakerless ignition retro-fits. However, as Ron wrote, the DuraSpark I module, with red wiring strain relief, is the superior module. It was only installed in cars destined for the green state (California) where emission standards were stricter. If you price them, you'll find the DuraSpark I module is quite a bit more expensive, which is why Ford didn't use them in more cars.
cowboy from hell
My module does not have a blue wire (what would it do?) and another thing, not important I guess, is the wires leaving the module are not in the same order.
I've got green, pink, black, purple, orange, white, and another black that's grounded to one of the module mounting screws.
I think I'll get the manifold and carb installed and get it running before I change anything, then I'm going to try and find a red DS1 module and a new coil and rewire to match your schematic. I'll have to reset my initial timing at this point too right? That and the new starter should ease hot starts.
It looks as if it would be relatively simple to install engine bay ignition and starter bypass switches when doing this rewire. Maybe use a DPDT switch to allow control from the ignition key switch (normal operation) or from an SPST (ignition)and a momentary (cranking) in the engine bay. Power for the engine bay switches would be fused but come directly from the battery via the starter solenoid.
Might be nice to have this isolated system to get you home in the event of cabin ignition switch failure or other electrical gremlins.
What do you think?
I've got green, pink, black, purple, orange, white, and another black that's grounded to one of the module mounting screws.
I think I'll get the manifold and carb installed and get it running before I change anything, then I'm going to try and find a red DS1 module and a new coil and rewire to match your schematic. I'll have to reset my initial timing at this point too right? That and the new starter should ease hot starts.
It looks as if it would be relatively simple to install engine bay ignition and starter bypass switches when doing this rewire. Maybe use a DPDT switch to allow control from the ignition key switch (normal operation) or from an SPST (ignition)and a momentary (cranking) in the engine bay. Power for the engine bay switches would be fused but come directly from the battery via the starter solenoid.
Might be nice to have this isolated system to get you home in the event of cabin ignition switch failure or other electrical gremlins.
What do you think?
George,
Heres what I found on the 335 Forum
strain relief info:
Red - Duraspark I (California cars 1977, California 302 V8 only, 1978-1979)
higher output, considered the module to use back in the '70s and '80s. Does
not employ a balast resistor. Senses current flow through the coil & adjusts
dwell for maximum spark intensity.
Blue - Duraspark II (49 state 1977, 50 state 1978 and later)
Yellow - Duraspark II with "dual mode" (except 1981)
White - Duraspark II with "cranking retard"
Brown - Duraspark III and other EEC controlled systems
Yellow - universal ignition module (1981)
Green - early solid state ignition (pre-1977) similar to Duraspark II, but
never popular for retrofitting, probably because the Duraspark I was
superior.
What would be the module best to use?
I think I have read here to use the red one due to the higher output?
What is your opinion on that?
Thanks a lot
Ralf
Heres what I found on the 335 Forum
strain relief info:
Red - Duraspark I (California cars 1977, California 302 V8 only, 1978-1979)
higher output, considered the module to use back in the '70s and '80s. Does
not employ a balast resistor. Senses current flow through the coil & adjusts
dwell for maximum spark intensity.
Blue - Duraspark II (49 state 1977, 50 state 1978 and later)
Yellow - Duraspark II with "dual mode" (except 1981)
White - Duraspark II with "cranking retard"
Brown - Duraspark III and other EEC controlled systems
Yellow - universal ignition module (1981)
Green - early solid state ignition (pre-1977) similar to Duraspark II, but
never popular for retrofitting, probably because the Duraspark I was
superior.
What would be the module best to use?
I think I have read here to use the red one due to the higher output?
What is your opinion on that?
Thanks a lot
Ralf
Ron, I think that list was written by me, I copied it from a Chilton manual. I'll give you guys the real "meat".
Ford 1970's ignition modules 101:
Breakerless ignition showed up in North American Ford vehicles in 1974. The first ignitions were not called DuraSpark, they were referred to as breakerless ignitions. The modules had a green wire strain relief with two harnesses, one connecter with 3 pins, and one with 4 pins. These modules "could" vary as to which wires were grouped in which harness, so you had to be mindful when working on these cars, to make sure the person behind the parts counter gave you the right replacement.
In 1977 Ford began referring to the breakerless ignitions as DuraSpark ignitions, and released two modules simultaneously; the DuraSpark I for California, and the DuraSpark II for the rest of North America. The DuraSpark I module was capable of producing a stronger and more consistent spark under varying engine load conditions which Ford found necessary to meet California emissions standards in 1977. Both DuraSpark modules featured spark retard when starting the motor. I am uncertain if that feature was incorporated into the earlier module. Both DuraSpark modules had two harnesses, one with a two pin connector, and one with a 4 pin connector, 6 wires in total. The earlier module with the green strain relief had 7 wires, it had a blue wire that was not carried over into the DuraSpark modules.
The DuraSpark I module had a red wiring strain relief. It was a very sophisticated ignition module, sensing & controlling the currrent in the coil primary as a means of controlling the current and spark quality produced in the coil secondary. It was only installed in California cars, therefore many hot rodders were not and are still not aware of its existence, or the difference between it and the DuraSpark II module. In 1978 Ford found it could meet California emissions regulations with the less expensive DuraSpark II module in all of its motors except the 302 V8. So California cars with the 302 V8 received the DuraSpark I ignition, and California cars equipped with all other motors got the DuraSpark II ignition like the rest of North America. The same applies to 1979 California cars. 1979 I believe was the last year DuraSpark I was installed in any Ford car. Worthy of mention is the safety feature built into the DuraSpark I module; if the distributor rotor is not turning, the module shuts off current to the coil primary, the ignition cannot fire, so it is safe to work on the ignition without fear of being shocked. NOT SO with any other Ford module. Disconnecting the wrong wire on any other Ford module while you are working under the hood can result in triggering the ignition and shocking you with enough current to stop your heart.
The DuraSpark II module introduced in 1977 has a blue wiring strain relief. It is not much different from the early module with green wiring strain relief. Its reliable and provides a nice spark, but it is less sophisticated than the DuraSpark I. Current in the coil primary is controlled just like it was with a breaker point ignition, with a ballast resistance in line with power to the coil. To provide a hotter spark while starting the motor, there is a second wire supplying the coil that bypasses the ballast resistor to provide full battery voltage when the ignition key is in the start position. This module is the most common module for retro-fitting breakerless ignition to early cars, simply because many people are not aware of the existence of the DuraSpark I module, or they are not aware of the differences. Its also worth mentioning this module can kill you while you are working on the motor unless precautions are taken to avoid an accidental discharge of the ignition!
After 1977 Ford developed other ignition modules with white, brown or yellow wiring strain reliefs that have other features that are unneeded or even undesireable for retro-fitting breakerless ignition. I found in my experience with them that all of the other modules had 3 wiring harnesses. They are designed to work with input from sensors, such as knock sensors, altitude sensors, MAP sensors, etc, and they are designed to control spark timing based on those inputs, to compensate for knock, altitude, engine load, etc. Or they are designed to work in conjunction with Ford's early "EEC" engine management systems. Some of these modules were called DuraSpark II, others DuraSpark III, and beginning in 1981 there was also the "universal" module.
Installation Notes:
1. When purchasing a module for your car, buy it from Ford! The Ford manufactured modules are very reliable. Reliability of the aftermarket modules is hit or miss.
2. DuraSpark modules use a high voltage coil made specifically for DuraSpark ignition. Use the Ford DuraSpark coil or DuraSpark specific replacement. Do not use a breaker point ignition coil.
3. DurSpark coils are oil filled and must be mounted oriented vertically, with the top higher than the bottom. They must not be mounted laying horizontally.
4. Painless Wiring sells a wiring harness for DuraSpark II conversions. It should be applicable for DuraSpak I conversions too, as there is very little difference in the wiring between the two ignitions. It is available at Summit Racing under part number PRF-30812, or JEGS under part number 764-30812.
5. DuraSpark distributors for the 351C will be sourced from a 1977 through 1982 Ford vehicle equipped with a 351M, 400 or 460 cubic inch V8.
6. A ballast resistor suitable for DuraSpark II installations is available from NAPA Auto Parts, NAPA part number ICR23 (1.2 ohms).
cowboy from hell
Ford 1970's ignition modules 101:
Breakerless ignition showed up in North American Ford vehicles in 1974. The first ignitions were not called DuraSpark, they were referred to as breakerless ignitions. The modules had a green wire strain relief with two harnesses, one connecter with 3 pins, and one with 4 pins. These modules "could" vary as to which wires were grouped in which harness, so you had to be mindful when working on these cars, to make sure the person behind the parts counter gave you the right replacement.
In 1977 Ford began referring to the breakerless ignitions as DuraSpark ignitions, and released two modules simultaneously; the DuraSpark I for California, and the DuraSpark II for the rest of North America. The DuraSpark I module was capable of producing a stronger and more consistent spark under varying engine load conditions which Ford found necessary to meet California emissions standards in 1977. Both DuraSpark modules featured spark retard when starting the motor. I am uncertain if that feature was incorporated into the earlier module. Both DuraSpark modules had two harnesses, one with a two pin connector, and one with a 4 pin connector, 6 wires in total. The earlier module with the green strain relief had 7 wires, it had a blue wire that was not carried over into the DuraSpark modules.
The DuraSpark I module had a red wiring strain relief. It was a very sophisticated ignition module, sensing & controlling the currrent in the coil primary as a means of controlling the current and spark quality produced in the coil secondary. It was only installed in California cars, therefore many hot rodders were not and are still not aware of its existence, or the difference between it and the DuraSpark II module. In 1978 Ford found it could meet California emissions regulations with the less expensive DuraSpark II module in all of its motors except the 302 V8. So California cars with the 302 V8 received the DuraSpark I ignition, and California cars equipped with all other motors got the DuraSpark II ignition like the rest of North America. The same applies to 1979 California cars. 1979 I believe was the last year DuraSpark I was installed in any Ford car. Worthy of mention is the safety feature built into the DuraSpark I module; if the distributor rotor is not turning, the module shuts off current to the coil primary, the ignition cannot fire, so it is safe to work on the ignition without fear of being shocked. NOT SO with any other Ford module. Disconnecting the wrong wire on any other Ford module while you are working under the hood can result in triggering the ignition and shocking you with enough current to stop your heart.
The DuraSpark II module introduced in 1977 has a blue wiring strain relief. It is not much different from the early module with green wiring strain relief. Its reliable and provides a nice spark, but it is less sophisticated than the DuraSpark I. Current in the coil primary is controlled just like it was with a breaker point ignition, with a ballast resistance in line with power to the coil. To provide a hotter spark while starting the motor, there is a second wire supplying the coil that bypasses the ballast resistor to provide full battery voltage when the ignition key is in the start position. This module is the most common module for retro-fitting breakerless ignition to early cars, simply because many people are not aware of the existence of the DuraSpark I module, or they are not aware of the differences. Its also worth mentioning this module can kill you while you are working on the motor unless precautions are taken to avoid an accidental discharge of the ignition!
After 1977 Ford developed other ignition modules with white, brown or yellow wiring strain reliefs that have other features that are unneeded or even undesireable for retro-fitting breakerless ignition. I found in my experience with them that all of the other modules had 3 wiring harnesses. They are designed to work with input from sensors, such as knock sensors, altitude sensors, MAP sensors, etc, and they are designed to control spark timing based on those inputs, to compensate for knock, altitude, engine load, etc. Or they are designed to work in conjunction with Ford's early "EEC" engine management systems. Some of these modules were called DuraSpark II, others DuraSpark III, and beginning in 1981 there was also the "universal" module.
Installation Notes:
1. When purchasing a module for your car, buy it from Ford! The Ford manufactured modules are very reliable. Reliability of the aftermarket modules is hit or miss.
2. DuraSpark modules use a high voltage coil made specifically for DuraSpark ignition. Use the Ford DuraSpark coil or DuraSpark specific replacement. Do not use a breaker point ignition coil.
3. DurSpark coils are oil filled and must be mounted oriented vertically, with the top higher than the bottom. They must not be mounted laying horizontally.
4. Painless Wiring sells a wiring harness for DuraSpark II conversions. It should be applicable for DuraSpak I conversions too, as there is very little difference in the wiring between the two ignitions. It is available at Summit Racing under part number PRF-30812, or JEGS under part number 764-30812.
5. DuraSpark distributors for the 351C will be sourced from a 1977 through 1982 Ford vehicle equipped with a 351M, 400 or 460 cubic inch V8.
6. A ballast resistor suitable for DuraSpark II installations is available from NAPA Auto Parts, NAPA part number ICR23 (1.2 ohms).
cowboy from hell