The Double Spark Doctrine Paradox

Topics Last Day Last Week Tree View    Getting Started Formatting Troubleshooting Program Credits    New Messages Keyword Search Contact Moderators Edit Profile Administration
Model T Ford Forum: Forum 2017: The Double Spark Doctrine Paradox
Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Saturday, January 14, 2017 - 10:54 am:

Adjusting coils by accurately measuring the dwell time to fire and setting the points on all 4 coils for equal firing time has been growing in popularity and receiving consistent reviews of remarkably smooth engine performance. Users knowledgeable with other coil test methods which use coil current as an indirect approximation of coil firing time were skeptical of the reported superiority of coils accurately adjusted for equal firing time and were quick to test those coils into their trusted HCCT and got a surprise; the coils adjusted for equal firing time violated the Double Spark Doctrine: (Single Spark = GOOD, Double Spark = BAD). This observation created controversy between folks with considerable experience testing and adjusting coils. Months of research and testing was necessary to understand why coils that achieve exceptional engine performance produce double sparks when tested on the venerable HCCT.

Turns out proper HCCT coil adjustment is much more complicated than simply applying the Double Spark Doctrine to achieve best results. Coils that produce double sparks on an HCCT can indicate improper coil adjustment but not necessarily indicate improper coil adjustment. The research confirms coils adjusted using the dwell time to fire method of coil point adjustment can produce double sparks when tested on an HCCT but do not exhibit the same characteristics as a double sparking coil known to yield poor engine performance.

For those interested in the details why can read the full article here: http://www.modeltecct.com/uploads/The_Double_Spark_Doctrine_Paradox_V5.pdf


Top of pagePrevious messageNext messageBottom of page Link to this message  By George John Drobnock on Saturday, January 14, 2017 - 11:16 am:

Even with such a crappy ignition system 15 million cars were produces - and maybe even 15 million were sold with such a poorly designed ignition. On top of that maybe 150,000 cars survived. With such a rough running electrics, the 21st century technology will prove that The Hungarian engineers were wrong in their primitive electronics and electrical design..


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Saturday, January 14, 2017 - 11:23 am:

George, That clearly is not what the article states. My question would be. Did you read it and understand it?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dave Dufault on Saturday, January 14, 2017 - 12:14 pm:

Not so long ago the life expectancy of a human was ---what - 30 -40 - years or so? Maybe longer or shorter depending upon the challenges of the area in which the creature lived.

These days with the advances in medicine - health care - knowledge of what works well within the body, might I add "organ transplants" - we current inhabitants seem to think this is progress.

So, what is so terrible about a little progress with old machinery? Sealed bearings in generators & starters, better voltage regulating devices for said generators...better spark generating devices for the explosive mixture in the numerous cylinders? So many advances in technology, it's hard to comprehend...computers, airplanes, "moon missions" - and beyond...


Some folks want to keep their original hips, knees, livers & kidneys...then other folks jump at the chance of improving their living conditions.

To each his own, no?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Saturday, January 14, 2017 - 12:42 pm:

The topic of controversy addressed here is coil testing methodology: Directly, accurately measuring time to fire spark using modern electronics technology versus indirectly, approximately measuring time to fire spark using vintage technology by measuring average coil current.

At no time were any stock Model Ts endangered, injured or harmed with the introduction of any modern electronics in any way, shape or form. Coil testing and adjusting is done by removing the stock coils from the stock car, testing them, adjusting them without altering their fundamental design, then re-installing the adjusted stock coils back into the stock car to operate the precise way Henry designed them to operate in the stock Model T using all the originally specified equipment in the original way they were originally designed to operate.


Top of pagePrevious messageNext messageBottom of page Link to this message  By George John Drobnock on Saturday, January 14, 2017 - 01:05 pm:

Since I have been on and off again with the forum, there has be discussion about the merits of or lack of merit for Double Sparking. With the discussion about the issue of Double Sparking, the early editions of Dykes discuss the question. There is nothing new in this dialogue. Except it does promote pro and con comments.

I have a HCCT and a coil tester. I set up my coils so that on first crank they buzz and the engine runs. I achieve may be 67 to 75 % efficiency. I want to drive the car - not analyze if it is possible to make it run at 100%. My HCCT does lead to discussions, it does look good on the shelf.

Yes I did read the article and yes there is merit in the comment - "Thus the lore of the Double Spark Doctrine: Single Spark = GOOD, Double Spark = BAD."

So gentlemen - does you engine start? Are you hitting on all four? If the answer is yes. That is good.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Saturday, January 14, 2017 - 01:08 pm:

Mike,
Please tell us how you actually adjusted the coils to get the smoother running engine.

Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Saturday, January 14, 2017 - 01:22 pm:

Norman, by accurately measuring the coil dwell time to fire spark and setting all 4 coils for the exact same dwell time to fire spark under simulated engine operating conditions. The consensus, including from some very experienced coil rebuilders, is a remarkably smoother engine performance compared to other methods of coil adjustment. See: http://www.modeltecct.com/ECCT_Reviews.html to read actual experiences using this method of coil point adjustment.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ken Todd, ............Red Deer, Alberta on Sunday, January 15, 2017 - 10:46 am:

If a Single Spark = GOOD, why is a Double Spark = BAD?
I would think that any spark after the initial one wouldn't hurt anything, if anything maybe improve the fuel burn.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Sunday, January 15, 2017 - 11:48 am:

Ken, the answer to your question is stated in the first paragraph of the referenced article.

You can also perform a forum search for the term "Double Spark" and receive many threads where Double Sparking is discussed in more detail.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Michael Deichmann, Blistrup, Denmark on Wednesday, February 01, 2017 - 12:48 am:

Ken, you have a certain amount of energy build up in the magnetic field during a cycle. If you split that energy in two or even 3 sparks, each spark will be weaker. Thats why we want all the energy fired in one spark.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Wednesday, February 01, 2017 - 07:25 am:

Indeed Michael D it is that simple. You are correct sir.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 07:41 am:

Indeed Royce the results of having all 4 coils set for equal firing time results in improved engine performance. It is that simple sir.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gary Tillstrom 30 miles N of Memphis TN on Wednesday, February 01, 2017 - 08:09 am:

"I think the Ford Engineers had it right based on the data presented herein. Coils that do produce double sparks on the HCCT could actually be advisable over coils adjusted to produce a single spark."

You have taken that out of context and you know it. They were clearly talking about cold weather hand cranking on mag. With a draggy clutch and oil at zero degrees they can be difficult to spin quickly to the point of starting on mag. Coils set to double spark (which is a weaker spark) would be easier to get to spark under cold conditions. Ford's advertisement clearly states "Cold weather". You overlooked where they state that ordinarily it is advisable to set them to single spark.

Your presentation of this as "Scientific" would be like someone inventorying refrigerators and upon finding insulin stored in them along with a resident with diabetes, make the proclamation that "storing insulin in the refrigerator causes diabetes". This can be proven by the fact that households without insulin in the fridge had no residents with the issue. You've reached your pre-determined conclusion.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 08:33 am:

I cannot understand how an engine that has coils firing at different advance and retard times could possibly run better than an engine that has coils with the same firing times.

To understand the effects of double sparks you have to be able to understand this. Ford did not have this information.
http://www.modeltecct.com/uploads/The_Double_Spark_Doctrine_Paradox_V5.pdf


Top of pagePrevious messageNext messageBottom of page Link to this message  By James A. Lightfoot on Wednesday, February 01, 2017 - 09:08 am:

Great article, my question is, Can the ECCT be used on Heinz coils? As well as on the later coils? Thanks Jim in Colorado


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Wednesday, February 01, 2017 - 09:22 am:

Gary,

Ford's advice to set coils for a single spark was completely valid and true, given the technology they had on hand at the time. It's still true, (or at least good advice), if you're still using Model T era technology to set your coils.

Mike sets coils using a different method, and in doing so, finds that some of the "old rules" do not apply, WHEN USING HIS METHODS. I don't believe he's saying that you should change your techniques or rejection criteria while using YOUR methods.

Once you take the past politics out of the equation it's quite interesting.


Top of pagePrevious messageNext messageBottom of page Link to this message  By George John Drobnock on Wednesday, February 01, 2017 - 09:25 am:

From 1913, the definition of and advantage of Double Spark Ignition - Ignition which is effected by two sparks produced simultaneously at two separate points in the combustion space of a gas motor, the object being to secure a more rapid combustion of a fuel charge. A Dictionary of Automobile terms.

To add to this discussion, certain ignition systems allowed for two sparking plugs per cylinder. Could the unintended consequences of the Ford coils double sparking be Ford's way to compensate for not having two sparking plugs?

This maybe an apples and oranges as discussion of the definitions being bantered about.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 09:34 am:

I do not have a Heinz coil, but i would expect that the physical size of the Heinz coil would have to be the same as the modern coil in order for it to fit into the Ecct test box.

xxx


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Wednesday, February 01, 2017 - 10:51 am:

George
In response to your posting of 9:25 am;
The short answer is NO
Engines with twin plugs (aircraft and BB Rajo for instance) have the plugs located at opposite sides of the combustion chamber. Some early car engines had dual plugs side by side, but generally they actually had two separate ignition systems, but typically only ran on one


Top of pagePrevious messageNext messageBottom of page Link to this message  By George John Drobnock on Wednesday, February 01, 2017 - 11:13 am:

Les, I am aware of the use of dual sparking plugs commonly called dual ignition... Just passing on a comment and view from 1913. Also I am surprised that this discussion has not mentioned that one possible cause of double sparking is a faulty cushion spring.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Chris Barker, Somerset, England on Wednesday, February 01, 2017 - 11:31 am:

Mike,
excellent paper. Thank you.
For those of us who invested in an HCCT or Strobospark before you stunned the world with the ECCT, is there any key parameter to getting consistent time-to-spark?
I might expect that greater cushion spring travel, or points gap might delay the spark. Is that how you set the coil which fired later?


Top of pagePrevious messageNext messageBottom of page Link to this message  By James A. Lightfoot on Wednesday, February 01, 2017 - 11:35 am:

Arnold, the physical size is almost the same, but the side contacts are different and lower. Thanks for your input. Jim


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Wednesday, February 01, 2017 - 11:42 am:

Michael, unfortunately, it really isn't as simple as that. You are partially correct in stating a single spark is preferred because it has greater spark energy available to initiate combustion under adverse conditions. The other detail you can not simply ignore associated with the performance impacting double spark is the spark timing; the first weak spark fires early whereas the 2nd weak spark fires late; which could actually be beneficial during hand cranking. The real problem occurs if the double sparking continues to occur at normal engine speed where ignition timing is more critical and noticeable (see below).

Gary, I do concede your point about cold starting under adverse conditions. A weak spark is less likely to initiate combustion under adverse cold staring conditions and a 2nd weak spark provides greater probability of ignition while hand cranking; the timing error is insignificant at such low engine speed, however, I also believe engine performance remained satisfactory After starting for Ford Engineers to state what they stated. That tells me the double spark they experienced was the "advisable" double spark that ceases to occur at normal engine speed, not the dreaded double spark that remains even at normal (albeit lower) engine speed with notable performance degradation; especially during hill climbing at lower engine RPM. The advisable double spark does not exhibit the same behavior because it only occurs at abnormally slow (hand cranking) engine speed and ceases to occur at normal engine speeds (>250RPM) according to the test data.

Jerry, the Model T ignition system operation is very interesting indeed. In fact, I find it truly fascinating how all elements function in concert when everything is properly adjusted.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Wednesday, February 01, 2017 - 11:53 am:

Chris, you are exactly correct. Cushion spring travel is paramount in attaining consistently firing coils. Ron Patterson and John Regan identified this long ago and understand they worked diligently to convince the point vendor to control the limits on travel better.

I recently had a set of brand new points (don't know the manufacturing vintage) with almost 0.030" of cushion spring travel! I could not get them to fire consistently regardless of the combination of point gap, vibrator spring tension and cushion spring tension; the 3 adjustable variables. The point were not useable so the point owner attempted to compress the limit rivet using a punch and hammer with nothing to lose. He brought the travel down to about 0.010" and the firing consistency of >90% was easily attained. Independent test data I took on limit rivet travel correlated very well with Ford's recommendation of 0.005".


Top of pagePrevious messageNext messageBottom of page Link to this message  By Brian Beatty _Kansas City on Wednesday, February 01, 2017 - 01:47 pm:

This stuff is way, way over my desire to learn and understand.

My biggest problem is I currently have a coil stuck in my ECCT. Gotta figure out a way to get it out without breaking anything... :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Wednesday, February 01, 2017 - 01:59 pm:

In fact double sparks occur at all engine speeds below maybe 25 MPH in high gear. You can easily prove this using a Strobe O spark which tests coils using an AC signal that is available in three engine speeds to duplicate idle, mid range, and typical Model T high RPM. The input to the coil from a Strobo Spark is nearly identical to that supplied by a typical Model T magneto, yielding optimum coil performance compared to coils set using any other device. Double sparks are displayed in real time.

The problem for Model T owners is that if a single coil is double sparking, and all the other coils are not, then you have one cylinder firing at a different time than the other three. Conversely, if you were to intentionally use four coils all set to double spark, then you have four weak coils that are going to yield low spark energy, leading to fouled spark plugs. This is not debatable, it is a statement of fact.


Top of pagePrevious messageNext messageBottom of page Link to this message  By James Baker on Wednesday, February 01, 2017 - 02:08 pm:

I can adjust mine pretty good by ear.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 02:40 pm:

Royce the ECCT not only checks for double sparks it gives you the spark energy (mj),coil firing current(A),primary inductance(mH)and best of all it gives you the COIL DWELL TIME (ms).It even tells you when to increase and decrease the vibrator spring tension. IT also checks the capacitor value in (uf) and gives you the leakage resistance (ohms)

My own personal observation has been that I have found that coils that might have carbon trais, as result of shorting of the secondary in their history will not have a good leakage reading, or as high as other coils. I recently had such a coil that failed internally while testing. All the information that the ECCT has available is not necessary needed to adjust a coil but it does help if you understand how a coil operates. JMHO


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 02:56 pm:

I'm sorry I did not mention that you need the software package to get the value readings.

And i misspelled the word trail.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 03:44 pm:

Quote from Strobo Spark instructions:

"This "ramp to fire" time (RTF) is
ideally equal in all coils to result in accurate cylinder to cylinder timing."

"The RTF of the coil for this "first spark" is different than the RTF for subsequent sparks."

Quote from ECCT instructions:

The
ECCT permits point adjustment by coil dwell time to fire so that each coil can be precisely
adjusted to minimize coil to coil (cylinder to cylinder) ignition timing variation for optimal
engine performance.

I have both tools the ECCT measures time the Strobo Spark does not.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Wednesday, February 01, 2017 - 03:55 pm:

Arnold,

The premise of my last post was that if one thinks that double sparks are good, then one must adjust all coils to double spark in order that they spark at exactly the same time, and accept low spark energy as a consequence of that choice.


Top of pagePrevious messageNext messageBottom of page Link to this message  By George John Drobnock on Wednesday, February 01, 2017 - 04:02 pm:

Not to take away from others, but it needs to be pointed out that in the Ford Owner February 1927, Adjusting the Coil Unit, by Murray Fahnestock, he wrote (using a HCCT, ) "If more than one spark occurs at any of the 16 points, this indicates that the cushion spring is not working freely. This can be corrected by lightly tapping the vibrator on the cushion spring rivet."
A is the cushion spring, .005" is the go/nogo measurement.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 07:42 pm:

Royce,
The paper that Mike wrote is 15 pages long and the most detailed and informative information about double sparking that I have ever seen. It will take me a long time to study it and hopefully understand most of it.

That being said, from what I understand,coils adjusted on the ECCT only double spark when tested on the HCCT at ABNORMALLY slow engine speed (below 250 RPM). Properly adjusted ECCT coils DO NOT double spark at normal Model T engine speeds (500-2500RPM).

Also, that the test pulse that represents the Model T magneto should be fast to emulate engine speed near the upper end, around 2000 RPM where ignition timing is most critical. The strobe spark operates at 450 RPM which is at the very low end of normal engine operation where ignition timing is more forgiving and least noticeable on performance.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Wednesday, February 01, 2017 - 08:06 pm:

Arnold,

Then you are simply mistaken. Any coil that double sparks on a HCCT also double sparks on a Strobo Spark and vice versa.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 09:06 pm:

So, than we agree that coils may double spark at low speeds, but what happens at the normal engine speeds is what we are interested in.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Wednesday, February 01, 2017 - 10:11 pm:

Coils double spark at all but the highest possible engine speeds which may never be attained if you are losing power at all other speeds.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Wednesday, February 01, 2017 - 10:30 pm:

I will read and study Mikes paper. I am hoping that he explains the factors that effect double sparks in relation to engine speed, to be honest I presently do not know.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Rick Olson on Wednesday, February 01, 2017 - 11:34 pm:

Time to fire up the dynamometer and test the performance of coils adjusted by the 3 different processes. Maybe this was already done by Mike in Tulsa. Data talks bull-butter walks.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Thursday, February 02, 2017 - 12:32 am:

To get meaningful data from a dyno test, you would have to test 100 engines with coils adjusted by 100 people on all 3 tools. (HCCT,ECCT,strobo spark). That is just not going to happen.

The testimony of users of a product is very conclusive evidence of a products performance.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Noonan - Norton, MA. on Thursday, February 02, 2017 - 12:53 am:

Arnold, are you just overly enthusiastic of this product,...or are you just trying your best to promote something here while pretending to be impartial? We have infomercials here all the time, and people see right through it.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gary Tillstrom 30 miles N of Memphis TN on Thursday, February 02, 2017 - 07:45 am:

If it would take 100 people to produce meaningful data, I have to ask, how is that even possible with such "far superior" performance?

There isn't much difference between a T set up correctly on coils as opposed to distributor (I think that has in fact been measured on a dyno). How can there be such a spread in performance between one set on a HCCT and the ECCT?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tim Rogers - South of the Adirondacks on Thursday, February 02, 2017 - 07:52 am:

There's also the placebo effect to consider.

Does it really run better or have I convinced myself it does because I spent the money?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ed Baudoux Grayling Michigan on Thursday, February 02, 2017 - 08:04 am:

It amazes me, how many of us will crucify someone who provides a product for our hobby. Do you think Mike is living "high on the hog" with all the millions in profits from his work? Where is this negativity rooted? If I were to formulate a plan for producing an automotive product, it sure would NOT be aimed at the Model T Ford market. We are a notoriously cheap group of stingy bastards. :-) Surely it would be more profitable to make an accessory for a Cadillac Escalade, or Corvette? I've only seen one report from an enthusiast who used Mike's coil tuning tool that didn't like it. ONE.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Thursday, February 02, 2017 - 08:43 am:

Let me try and make this clear. I personally went to Kentucky and bought my HCCT from Ron Patterson. He'S a great asset to the hobby and an expert on the Model T electrical system. I have a Strobo Spark from Fun Products and bought an ECCT from Mike Kossor. I have zero financial interest in any of these products.

I happen to enjoy restoring and adjusting Model T coils. I have rebuilt about 100. I am not an expert on coils or the Model T Ford. We all should enjoy the hobby and use the tools we prefer. I think you are correct, I am overly enthusiastic about the ECCT. I happen to have all the products and wanted others to have the benefit of my experience.

All I can say is use and enjoy your cars.


Top of pagePrevious messageNext messageBottom of page Link to this message  By James A. Lightfoot on Thursday, February 02, 2017 - 10:59 am:

Mike, can the ECCT test 1912 Heinz Coils? As the contacts are different and I understand their amp reading is lower than the 1.3 of later coils. Thanks Jim


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Thursday, February 02, 2017 - 11:58 am:

James, yes, you can use it to adjust other types of coils, however, will need to build an adapter for the coil with proper spark gap because their physical dimensions will not permit insertion into the fixture. Then connect power, ground and timer terminals from the tester to the corresponding terminals on the adapter. Others have done this with good success.


Top of pagePrevious messageNext messageBottom of page Link to this message  By James A. Lightfoot on Thursday, February 02, 2017 - 12:09 pm:

Thanks Mike, just what I needed to know. Jim


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Thursday, February 02, 2017 - 12:36 pm:

Arnold,

I don't think Mike tested 100 different engines when he dyno tested for the E-Timer. Does that mean all his data is BS?

Ed,

I can't speak for others, but MY "Negativity" (As perceived by some), is from the wild claims of superiority with little to nothing more than seat of the pants testimonials to back it up. Even what little true test results have been brought forth show things to be all be in the same ball park and what differences there may be are measurable only by some expensive equipment, and even then sometimes in an rpm range that practically no one ever operates in. And this would all be just fine and dandy, if it weren't made to sound as if there was no comparison whatsoever, that these new high tech things were head and shoulders above the original system, and "FAR SUPERIOR". THAT is where my "Negativity" comes from.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Thursday, February 02, 2017 - 12:40 pm:

Hal

I have to question your assumptions.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Thursday, February 02, 2017 - 12:40 pm:

Arnold,

Please forgive me. Heaven forbid I put words in your mouth. Perhaps I should say "Does that mean none of Mikes data is "Meaningful"?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Thursday, February 02, 2017 - 12:43 pm:

The only thing I "Assumed" was that Mike did not test 100 engines. And I think that is a good assumption. However, if you know differently, I am certainly man enough to admit when I'm wrong. You?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Arnold on Thursday, February 02, 2017 - 12:45 pm:

I think it means that the E-Timer is a good product as well as the ECCT.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Thursday, February 02, 2017 - 12:51 pm:

See. Now THAT'S the way to word a statement. See the difference between what you just said and what you said last week? Few would throw this one back in your face.


Top of pagePrevious messageNext messageBottom of page Link to this message  By George John Drobnock on Thursday, February 02, 2017 - 01:12 pm:

So I have a question, I do not have any of the fancy toys, the HCCT or the ECCT, I rebuild a coil, just new points - what is the percentage that the coil will operate properly without double sparking? Provided that I follow the recommendations found in older Model T literature such as the Ford Owner February 1927, Adjusting the Coil Unit, by Murray Fahnestock, and following his suggestion that the cushion spring be set to working freely. Following the recommendation that the cushion spring has a gap of .005".


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Thursday, February 02, 2017 - 03:05 pm:

George,

It depends on your experience level and the quality of the points that you get. In general a Model T will run on all four on Battery with a wildly misadjusted set of coils. Double sparks are an impossibility when operating a coil on DC.

If you want to have the car run good on MAG then you need to have some way to properly adjust the points on AC voltage. Double sparking is one of the things that can lead to terrible performance on MAG.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gary Blake, Kansas City on Thursday, February 02, 2017 - 04:09 pm:

Thanks to all who are contributing to this controversial (to say the least) topic. As a newbie to T's I am nevertheless learning a lot about the mysteries of the T ignition system despite the lack of consensus, at least yet.

Royce, your last post re: A/C and double sparking got me thinking. Would 4 diodes in the timer/coil primary wiring eliminate any possibility of a double spark on mag?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Thursday, February 02, 2017 - 04:13 pm:

Gary,

No, that would simply turn the AC power into half wave rectified DC, lowering the voltage to the coils and reducing spark energy considerably at all engine speeds. I guess you could say that you "eliminated" double sparking because now you have low wattage DC but the car would run very poorly on MAG, and might not run at all at lower RPM due to voltage being cut in half.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Thursday, February 02, 2017 - 04:31 pm:

It is absolutely possible for a coil to produce double sparks operating on DC battery (or AC Magneto) and common due to improper point adjustment.

Here is test data of a coil that produces double sparks operating on 12VDC due to improperly adjusted points. The 1st weak spark (only 3.8A primary coil current) occurs early (0.00116 seconds) and the 2nd weak spark (only 3.7A) occurs late (0.00276 seconds). For reference, a properly adjusted coil will fire a single hot spark in 0.002 sec when the primary coil current reaches approximately 6A operating on 12VDC. This example and others are covered in the referenced article for the benefit of others interested in coil operation.


Double spark on 12VDC


Top of pagePrevious messageNext messageBottom of page Link to this message  By George John Drobnock on Thursday, February 02, 2017 - 04:31 pm:

To add to Gary's comment. The magneto produces AC voltage/current, if a step up transformer was inserted between the magneto and the diodes in question, would this increase spark energy to make the coils more efficient on DC?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gary Blake, Kansas City on Thursday, February 02, 2017 - 04:35 pm:

George,

No. There would be a net energy loss with the second conversion. As they say, "there is no free lunch"


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Thursday, February 02, 2017 - 04:53 pm:

Jeez Louise. Is it so hard to just adjust the cushion spring and get the damned double sparks out of it? I believe I would do that before adding diodes and transformers. CRAP!


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Sullivan on Thursday, February 02, 2017 - 06:24 pm:

I have to ask, while your oscilloscopes etc. are warmed up, did anybody check the average error in timing in the average timer? And will the T run on said timer and 4 ordinary coils? Always wondered. Dave in Bellingham,WA


Top of pagePrevious messageNext messageBottom of page Link to this message  By George John Drobnock on Thursday, February 02, 2017 - 06:36 pm:

Mr Davis. please calm down. If you remember I am one who sets my coils with a buzz box tester. And I am aware that the cushion spring is critical for proper coil operation. As for asking my question about the step up transformer -- well there was an opportunity to see what others think.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Thursday, February 02, 2017 - 07:29 pm:

No calming necessary. It just seems like going around your elbow to get to your ear, you know? I'm not going to address your use of a buzz box. That's your business. All I know is that a HCCT or a Strobospark (And depending on who you listen to, even the ECCT) will show double sparks and fixing them is pretty dang easy. No reason to add anything else to cover up a problem.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Chris Barker, Somerset, England on Friday, February 03, 2017 - 01:37 pm:

David,
you are right to question the timer. Having tried most types, I keep returning to the Anderson. The car just goes better!
However, it is about 4 times as sensitive to not being concentric with the camshaft as other types because of the shallow angle of the flapper.
I mounted one in my lathe (stationary) with the flapper held in the tool post. With this set up I was able to 'wind' the flapper away from the timer centre and check the effect on timing. The timer was connected to an ohm-meter.
A roller or brush timer will have a timing error of about 1 degree for 0.015" of offset (that's 2 degrees crank angle).
The Anderson is about 0.004" per degree.
I checked a brush timer on my car, and it wasn't as consistent between cylinders as I expected - I think the actual contact point is not as precise as you might expect. Not too different from Andersons I have checked.
HOWEVER within reason, it isn't important as long as you are running on magneto as you will find the 'sweet spot' and all 4 coils will fire on the same magneto peak.
It does matter if you run on DC.


Add a Message


This is a private posting area. Only registered users and moderators may post messages here.
Username:  
Password:

Topics Last Day Last Week Tree View    Getting Started Formatting Troubleshooting Program Credits    New Messages Keyword Search Contact Moderators Edit Profile Administration