Duraspark Distributor

John Ha

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Diddling around with the remanufactured Duraspark distributor for my 250 six (transplanted into my 66 Mustang). I was reading the "how to" recurve information on the Classic Inlines site (ci/DSIIswap.html#Recurve, Re-curve the Duraspark II for Improved Mileage).

When I follow the instructions I end up with the heavier spring being very loose on the posts after the tab is bent toward the distributor shaft - there's a bunch of slack before the spring will begin to have any effect. Is that the right thing to do or is there something different/better I should be doing?

I'd PM the fellow that wrote it (Mark P.) but he does not seem to be an active member any longer.

Thanks!
 

bubba22349

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Yes that's what will happen when you bend the tab forward, basically this allows the timing curve to advavance faster. For your first time trying to recurve a Distribtor It can take a good amount of time learning about tuning the ignition timing to then dial in the advance curve using a good quality timing light with either an accurately marked (degreed) Dampner or with timing tape. Plus than doing some road or race testing and retesting to calculate your improvements it can be a fun project and later with more experience the amount of time is greatly reduced. As far as if there's anything different or better the answer is yes you can also have this work done by a Pro that done this many times and uses a Distribtor machine to check and set the curve. Best of luck (y) :nod: Edited
 

John Ha

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bubba22349":1d0y9dip said:
Yes that's what will happen when you bend the tab forward, basically this allows the the timing curve to advavance faster. For your first time at doing a recurve It can take a good amount of time learning about tuning the ignition timing to dial in the advance curve using a good quality timing light with either an accurately marked (degreed) Dampner or with timing tape. Plus than doing some road or race testing and retesting to calculate your improvements it can be a fun project and later with more experience the amount of time is greatly reduced. As far as if there's anything different or better the answer is yes you can also have this work done by a Pro that done this many times and uses a Distribtor machine to check and set the curve. Best of luck (y) :nod: Edited

Thanks very much for the reply.

I will be brutally honest and say that I don't have a clue what I'm doing with this. I've read everything I could find and for whatever reason, still don't really comprehend what the criteria are. I guess this will be one of those things that I can do but not do well.

But I'll give this a shot and see how it works. If it doesn't work out well I'll probably bite the bullet and spend the money to have "our" recurve expert (wsa111) do it.
 

John Ha

Well-known member
I completed this mod (swapping the light spring with the lighter one and bending the post of the heavier spring about 3/32"). It feels like it's a little easier to start out and also feels a bit peppier around town. It was pretty easy - the most difficult part was getting the distributor clamp bolt threaded in again - but I did have to grind down the top of the bent post a bit so it cleared one of the "breaker plate" pivot rivets. Not a big deal.
 

bubba22349

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Have you looked at the Go Fast for less site it has some good general info and even a section on re cruveing in its ignistion section that goes into the Ford Distribtors pertty well, if not take a look at it http://www.gofastforless.com

Now If you really want to dive deeper into the old school arts of tuning, understanding of how an ignistion system works and how you can improve it, Distribtor re curving there are some older books that go into it and on tuning an engine for performance and or economy. I still happen to have somewhere a very good one that I read and studied it was written by the founder of Jacobs ignistions (CD Boxes seemular to the MSD) Chris A. Jacobs he has a PHD in Electrcal Enginering / Dr. Jacobs. See first link below for that book version, I don't think it's still in print. But here is a listing for a a couple used ones and the second is the third revised previous version of that book. I really like this book as it's very detail oriented which suits my personality to a T and recommend it to anyone. This is the copy I have think it's was the last revision of his four books on ignistions. https://www.amazon.com/Performance-Igni ... 63WNM7BTAA

This is the third Revised Edition I haven't had a chance to look at this version but i suspect that it is also a good book version. https://www.amazon.com/Doctors-Step-Gui ... 0965085600

Also there some Peterson publishing Hot Rod series books on carb's and ignistions that are quite decent too, going into the compleate systems and how they work together. But if I could only afford one that would be the above Jacobs book. Here one of their older books I haven't seen or read this version. https://www.amazon.com/Petersens-Basic- ... 0822750147

In more current books here are couple more that get into far more advanced systems and likely way over kill as far as working on the DuraSpark II system.

https://www.amazon.com/Build-Power-Dist ... HSMTHC1835

https://www.amazon.com/High-Performance ... CF2SRFTB9G

:beer: Congrats on your beginning re curve successes! Tuning for power and economy can be a lot of fun as well as rewarding in finding out what your engine likes. I have always enjoyed tuning all engines and even had my 250 six powered Maverick tuned so it could easily leave on the stock Ford and Chevy V8's from the stop light. Besides the above posted tuning tools some other helpful items will be a good Tach and a Vacuum gauge or two of them set up togeather. Best of luck (y) :nod:
 

wsa111

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If you want it done by a professional contact me.
viewtopic.php?f=46&t=79901
I will custom curve your DS11 for best performance & economy.
I use a Sun Distributor Tester to fine tune my mods. Bill
 

chad

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"...suits my personality..."
I can just C our ol friend bubs!
burnin da midnite oil book propped up,
a creased brow, finger upon the page -
a wild light gleaming from his eye !
:eek:
I remember U from past months John. Some of the difficult may B w/things unseen. By twisting the gear on the bottom, observing the internals, U will slowly understand. One thing that helped me was to realize the scissors like characteristics of the pates. As the dizzy is spun faster those plates kinda separate (well - move) out by centrifugal force. Anyway, just following the guides (no understanding) U will still "get there" (performance enhanced). I too have a long way to go, and? there's plenty time...
Enjoy !
 

John Ha

Well-known member
bubba22349":8nof4fcb said:
Have you looked at the Go Fast for less site it has some good general info and even a section on re cruveing in its ignistion section that goes into the Ford Distribtors pertty well, if not take a look at it http://www.gofastforless.com

Now If you really want to dive deeper into the old school arts of tuning, understanding of how an ignistion system works and how you can improve it, Distribtor re curving there are some older books that go into it and on tuning an engine for performance and or economy. I still happen to have somewhere a very good one that I read and studied it was written by the founder of Jacobs ignistions (CD Boxes seemular to the MSD) Chris A. Jacobs he has a PHD in Electrcal Enginering / Dr. Jacobs. See first link below for that book version, I don't think it's still in print. But here is a listing for a a couple used ones and the second is the third revised previous version of that book. I really like this book as it's very detail oriented which suits my personality to a T and recommend it to anyone. This is the copy I have think it's was the last revision of his four books on ignistions. https://www.amazon.com/Performance-Igni ... 63WNM7BTAA

This is the third Revised Edition I haven't had a chance to look at this version but i suspect that it is also a good book version. https://www.amazon.com/Doctors-Step-Gui ... 0965085600

Also there some Peterson publishing Hot Rod series books on carb's and ignistions that are quite decent too, going into the compleate systems and how they work together. But if I could only afford one that would be the above Jacobs book. Here one of their older books I haven't seen or read this version. https://www.amazon.com/Petersens-Basic- ... 0822750147

In more current books here are couple more that get into far more advanced systems and likely way over kill as far as working on the DuraSpark II system.

https://www.amazon.com/Build-Power-Dist ... HSMTHC1835

https://www.amazon.com/High-Performance ... CF2SRFTB9G

:beer: Congrats on your beginning re curve successes! Tuning for power and economy can be a lot of fun as well as rewarding in finding out what your engine likes. I have always enjoyed tuning all engines and even had my 250 six powered Maverick tuned so it could easily leave on the stock Ford and Chevy V8's from the stop light. Besides the above posted tuning tools some other helpful items will be a good Tach and a Vacuum gauge or two of them set up togeather. Best of luck (y) :nod:

Wow! Thank you!

I confess to being surprised that the configuration was OK - most times having loose parts on a car ends with bad things happening.

My stumbling block as far as understanding is how some the pieces of the engine system work together - distributor advance being one of those. I understand mechanically how the vacuum and centrif. advances work and what they do. Where I fall short is understanding how what they do and when they do it play into the engine system performance.

It's a hobby and I've learned a lot but have not gotten into the nitty gritty details of some things - this being one of them.

Bubba, thanks for the rainy day reading suggestions. :)

Many thanks and Cheers, John
 

bubba22349

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chad":271j7lev said:
"...suits my personality..."
I can just C our ol friend bubs!
burnin da midnite oil book propped up,
a creased brow, finger upon the page -
a wild light gleaming from his eye !
:eek:

:rolflmao: LOL well that's probably quite accurate Chad, most of this as it relates to my automotive pursuits and study happened while I was still a teenager so maybe not a creased brow . By 20 I had both of my A&P license ratings from the FAA, and then opened up an auto repair shop when there weren't any jobs in summer 1969 in the Aviation field.

But it sure dose resemble me today though in my older years (I certainly have lots of creases and wrinkles) that get quite contorted when studying History and trying to come to an understanding of how it relates to what's going on today. If you look at it you can see that they are still using the same old play book. (y) :nod:
 

bubba22349

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John Ha":z5fq54bj said:
Wow! Thank you!

I confess to being surprised that the configuration was OK - most times having loose parts on a car ends with bad things happening.

My stumbling block as far as understanding is how some the pieces of the engine system work together - distributor advance being one of those. I understand mechanically how the vacuum and centrif. advances work and what they do. Where I fall short is understanding how what they do and when they do it play into the engine system performance.

It's a hobby and I've learned a lot but have not gotten into the nitty gritty details of some things - this being one of them.

Bubba, thanks for the rainy day reading suggestions. :)

Many thanks and Cheers, John

Your welcome John, ok I'll take a shot at trying to shed some more light on how the Advance System works maybe it will bring you some more understanding. These DS II Distribtors are a marvel of Enginering, combining several sub systems into one compact unit. I learned these concepts on building a mini bike around 7 or 8 years old had picked up an old Brigs & Stratton engine that i then overhauled, it had a simple point operated magneto ignistion and no means of advanceing the Ignistion timing, learned that this simple system was all you need to get an engine run. Next at 13 I bought my first car a 1928 Model A Ford that I did a complete restoration on, it had a very simple point and condenser type Distribtor with a hand lever operated advance system. With this system I learned how advancing the timing effected the engines power output you could feel the engines power change by advanceing or retarding the Distribtor timing with that hand lever.

Moving on next Ford developed the Load O Matic ignistion systems a simple advance system using the carb Venturi and engine manifold Vacuum to advance the ignistion timing by sensing the engines load. Next phase is Fords even more modern Distribtors with its new duel system of centrical and vaccum advance yet still using the old reliable points and condesor, these came out on the 1957 Y Block V8's giving greater power and very good economy this system was used until 1974. This brings us to the next advancement of the DuraSpark I & II Distribtors with their electronic trigger yet both still have the same advance system. This advance system that's basically performs automaticity after its set up and assembly, that's still based on those advance system parts that Ford first used back on 1957 V8's having many interchangeable parts between them. As you can see Ford kept building and modding their ignistion system, I think that's enough for the History to cover this.

Now when we are only looking at the advance systems individual parts many of which can perform several functions. So we have these main parts, the Distribtors center shaft togeather with its cam driven gear on the bottom to turn the shaft, this center shaft also has the ability to be adjusted into two different advance timing curves limits (the notches limit the total advance) these are marked on the shaft. Simplly by taking the drive gear off the shaft and lifting up it is turned 180 degrees to be able to use the second advance curve. Then there is the advance weights and the springs that control the advance timing. Looking at the advance weights we have a combo of a flyweight (or counter weight) which moves outward from the effects of the Centrical force acting on them, this is depending on the center shafts operating RPM which is 1/2 of the engines RPM. The second function of these advance weights is that they have a Cam shape to them that acts against the center shaft and thereby turning it more and advancing the ignistion timing. See picture of advance weights showing they will move / advancing the center shaft with the centrivical force. http://www.gofastforless.com/ignition/advance.jpg
Lastly are the two springs that by their amount of tension act as some resistance as to how fast this timing advance comes into effect.

That brings us to the vacuum advance system that can also be tuned for better engine economy this system uses the engines manifold vacuum to add even more timing advance during times of higher engine vacuum. This higher engine vacuum ocures when the carburetor is at part throdle openings such as during any steady state driving, street, hyway, or freeway cruise speeds. Well there you have it hope that is of some help in understanding the advance systems. Best of luck in your tuning adventures. :nod: (y) Edited
 

John Ha

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bubba22349":33mx545n said:
Your welcome John, ok I'll take a shot at trying to shed some more light on how the Advance System works maybe it will bring you some more understanding. These DS II Distribtors are a marvel of Enginering, combining several sub systems into one compact unit. I learned these concepts on building a mini bike around 7 or 8 years old had picked up an old Brigs & Stratton engine that i then overhauled, it had a simple point operated magneto ignistion and no means of advanceing the Ignistion timing, learned that this simple system was all you need to get an engine run. Next at 13 I bought my first car a 1928 Model A Ford that I did a complete restoration on, it had a very simple point and condenser type Distribtor with a hand lever operated advance system. With this system I learned how advancing the timing effected the engines power output you could feel the engines power change by advanceing or retarding the Distribtor timing with that hand lever.

Moving on next Ford developed the Load O Matic ignistion systems a simple advance system using the carb Venturi and engine manifold Vacuum to advance the ignistion timing by sensing the engines load. Next phase is Fords even more modern Distribtors with its new duel system of centrical and vaccum advance yet still using the old reliable points and condesor, these came out on the 1957 Y Block V8's giving greater power and very good economy this system was used until 1974. This brings us to the next advancement of the DuraSpark I & II Distribtors with their electronic trigger yet both still have the same advance system. This advance system that's basically performs automaticity after its set up and assembly, that's still based on those advance system parts that Ford first used back on 1957 V8's having many interchangeable parts between them. As you can see Ford kept building and modding their ignistion system, I think that's enough for the History to cover this.

Now when we are only looking at the advance systems individual parts many of which can perform several functions. So we have these main parts, the Distribtors center shaft togeather with its cam driven gear on the bottom to turn the shaft, this center shaft also has the ability to be adjusted into two different advance timing curves. Then there is the advance weights and the springs that control the advance timing. Looking at the advance weights we have a combo of a flyweight (or counter weight) which moves outward from the effects of the Centrical force acting on them, this is depending on the center shafts operating RPM which is 1/2 of the engines RPM. The second function of these advance weights is that they have a Cam shape to them that acts against the center shaft and thereby turning it more and advancing the ignistion timing. See the picture of showing how these advance weight will act on / advanceing the center shaft. http://www.gofastforless.com/ignition/advance.jpg
Lastly are the springs that by their amount of tension act as some resistance as to how fast this timing advance comes into effect.

That brings us to the vacuum advance system that can also be tuned for better engine economy this system uses the engines manifold vacuum to add even more timing advance during times of higher engine vacuum. This higher engine vacuum ocures when the carburetor is at part throdle openings such as during any steady state driving, street, hyway, or freeway cruise speeds. Well there you have it hope that is of some help in understanding the advance systems. Best of luck in your tuning adventures. :nod: (y)

Thanks! :) :beer:
 

B RON CO

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Hi, as mentioned, I was also amused by Chad's description of going through a manual to fix something. My guy would have some tools and parts on the table and a greasy rag in his back pocket.
Anyway, John Ha, you can put a piece of vacuum hose on the vacuum advance cannister and suck on it and if it is good you will see the breaker plate advance, and it will stay there until you stop sucking. It will even stay advanced if you put the hose on your tongue.
Good luck
 

John Ha

Well-known member
B RON CO":4s61c6kj said:
Hi, as mentioned, I was also amused by Chad's description of going through a manual to fix something. My guy would have some tools and parts on the table and a greasy rag in his back pocket.
Anyway, John Ha, you can put a piece of vacuum hose on the vacuum advance cannister and suck on it and if it is good you will see the breaker plate advance, and it will stay there until you stop sucking. It will even stay advanced if you put the hose on your tongue.
Good luck
Happy to say that I did this before I put the distributor in. The vacuum advance works just fine (and I have the little circle impressions on my tongue to prove it!) but I did realize that I'd missed putting the breaker plate carrier stub into the hole of the advance arm. I'm glad I caught that before I put the distributor on the engine - much easier to fix on the bench. :)
 

B RON CO

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Hi, sure, the hard part is putting the little clip back in the groove. Many clips have gone off into orbit and are still circling the earth. Good luck
 

bubba22349

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HI John , so how are you doing on your Distribtor advance tuning? (y) :nod:
 

John Ha

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bubba22349":2w05qss5 said:
HI John , so how are you doing on your Distribtor advance tuning? (y) :nod:

I'm pretty happy with it. I did the spring change and tab bend per the instructions and it helped the bottom end quite a bit, as advertised.

I messed around with the initial timing a bit too and found a happy place for that, then made a brief foray into looking for an adjustable vacuum advance. No success there but I feel it's "good enough" and have moved on to the next challenge - learning about AC hoses and fittings so I can get the AC hooked back up.

I really appreciate all the help you and the others have given.

Thank you!
 

chad

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John Ha":121i7qod said:
and found a happy place for that
make sure its by instrument rather than other means:
dwell, timing light and vac guage.
Sure sound, feel, etc are 'good'nuff' but these help make 'optimal'
(y)
 

xctasy

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B RON CO":3tqx85db said:
Hi, sure, the hard part is putting the little clip back in the groove. Many clips have gone off into orbit and are still circling the earth. Good luck

Need
Another
Spark
Assembly.

Those two references from Un stobbable B Ron the Conquer and my badself were just what a spaceshipAccessory Technician needs right now.

Im off to Launch. Um. Lunch....
 

chad

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"NASA"
U already launched.
Drive safe I know its winter dwn there now... :chill: :cool:
Congrats on world toppin C-19 safety, keep it up ! :nod:
(y)
 
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