Newbomb Turk
Well-Known Member
I made this video to show the difference between a CDI ignition and an inductive ignition. Again, it’s not a one is better than another test, but to show the differences in spark energy and timing retard.
Follow up test with a CDI ignition
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A single point at 10,500 with very little retard. Amazing. Thanks tor the test.
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Newbomb Turk
Well-Known Member
That’s a single point distributor I grabbed out of a pile a couple of years ago for testing. I didn’t even check dwell or anything.
Maybe when it gets dark tonight I’ll grab a Mallory dual point distributor and test it as a stand alone ignition.
It won’t retard.
Have you ever tested a chrysler electronic distributor running HEI (4 pin) conversion? That is the set up I have in my Grey Van, which I will be tuning (per my latest video)
Love it!
Newbomb Turk
Well-Known Member
I have not. I should though.
That's good stuff, Tim. Thanks. So a single point ignition is good to 9 grand. LOL
With the right points. CH-14 4500 IN lb 15-17, CH15n in lb 22 is 6500 accel or mallory 28 in lb 10K Spring pressure so it does not float is the key here.
Gives me a whole new appreciation for my dual point Prestolite I set up with Ray’s advice (Thanks @halifaxhops !) in 361 Golden Commando.
No one on the street will rev that high. SB maybe 6500 B/RB 4500
Well, I've seen a few 7500 rpm LA Mopar street moments, but not for any greatly extended durations
!Turk,
Not trying to be argumenative, but offering a possible reason for the retardation. Timing lights typically use a Xenon lamp, not sure of the light source in your m/c. Either type, a certain amount of time is reqd for the lamps to come on [ illuminate ]. The crank does twice as many rotations at 6k compared to 3k. But the time period for the light to illuminate does not change with rpm. At 6k, the crank has rotated further before the timing light comes on...& shows up as retarded ign. So is the 'retard' [ or some of it ] the light playing 'catch up' because of increasing rpm?
Not trying to be argumenative, but offering a possible reason for the retardation. Timing lights typically use a Xenon lamp, not sure of the light source in your m/c. Either type, a certain amount of time is reqd for the lamps to come on [ illuminate ]. The crank does twice as many rotations at 6k compared to 3k. But the time period for the light to illuminate does not change with rpm. At 6k, the crank has rotated further before the timing light comes on...& shows up as retarded ign. So is the 'retard' [ or some of it ] the light playing 'catch up' because of increasing rpm?
Newbomb Turk
Well-Known Member
I’m not saying that’s not possible but how do you explain a points distributor showing no retard or very little retard?
I don’t know the answer to that.
And that of course goes back to using one timing light.
Using the dyno timing light, then going home and using your timing light (not you in particular but you as in anyone) and then going to the track, forgetting your timing light and borrowing a light at the track.
I’ve seen that before. You now have the potential for inducing error by 200%.
I need to buy a scope but I haven’t had time to look around and see what’s out there. I need to and eventually I’ll get one.
I am not doubting that there is some amount of retard in any ign system. Could it be due to coil differences? It is well known that there is retard with magnetic trigger ign due to distortion in the p/up signal as rpm increases.
I like that you used a point distributor this time. Very cool. It's also a diferent type of trigger signal. I think similar to a square wave pattern of a digital signal. I'm not saying you conclusion is wrong that this Mallory box has less retard than the hirev 7500 box. But you have introduced another varible by using the points distributor in place of the Chrysler electronic distributor. Just for the sake of arguement what if you triggered the Mallory box with the Chrysler electronic distributor and it retarded like it did with the hirev 7500 box? Is this a test you can do?
Newbomb Turk
Well-Known Member
That I’ve checked, just not with any of the Mallory 7 boxes. They only take one Mallory coil and two MSD coils but I don’t have theMSD coils.
I have tested with different coils and I never say any difference. I heave never tried an E coil but I have one here now I can use.
Newbomb Turk
Well-Known Member
Mattax
Just the facts, ma'am
The MSD boxes can also be triggered by points or magnetic pickup.
The extra challenge with the autotronics stuff is the MSD boxes fire multiple times in the low rpm range.
Timing lights can all have a delay due to their workings but the dial backs are for obvious reasons going to show the most slew.
That thread on moparts started because of a timing light
board.moparts.org
For how switching time relates to degrees Tuner posted:
"For some perspective do the math:
6000RPM / 60 seconds = 100 revolutions per second
100 revolutions per second X 360 degrees = 36,000 degrees per second.
Each degree is 1/36,000th of a second or .00002778 sec."
from Spark Lead (may have to join speedtalk to see this thread)
Multi-sparks and (some) timing lights
The extra challenge with the autotronics stuff is the MSD boxes fire multiple times in the low rpm range.
Timing lights can all have a delay due to their workings but the dial backs are for obvious reasons going to show the most slew.
That thread on moparts started because of a timing light
Mallory Unilite timing issue
Playing with a big block, chasing an off idle stumble. While checking the distributor, I noticed that the timing would retard as much as 8 degrees when I snapped the throttle. Made sure that the vacuum advance was disconnected to prevent false readings. Still the same result. Timing isn't ...
board.moparts.org
For how switching time relates to degrees Tuner posted:
"For some perspective do the math:
6000RPM / 60 seconds = 100 revolutions per second
100 revolutions per second X 360 degrees = 36,000 degrees per second.
Each degree is 1/36,000th of a second or .00002778 sec."
from Spark Lead (may have to join speedtalk to see this thread)
Multi-sparks and (some) timing lights
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MadScientistMat
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I'm also interested in seeing how the timing retard compares if you run the same CDI with an electronic distributor. These videos are very informative; thanks for posting them!
Post #18 was what I was getting at in the other post on inductive ign. The Xenon lamp in a timing light [ or any lamp for that matter ] takes a certain amount of time to turn 'on'. As rpms increase that time does not change, but the the crank dampener which has the timing markings, is moving faster with more rpm. If the dampener speed [ rpm ] outruns the lamp, it will show up as retarded ign. I tried to find the turn on time for Xenon lamps but could not find anything. Also, timing ights use an inductive ferrite clamp to 'read' the magnetic pulse of the spark; circuitry inside the t/light converts that pulse to an electric signal to turn on the lamp. All this takes time & there is less time as rpms increase. It could add to the retard that shows up when using the t/light.
Newbomb Turk
Well-Known Member
And no one is saying that timing lights don’t have slew rate. They do.
The question is does the retard shown on a distributor machine include some retard based the slew rate of the light on the machine.
The answer is it depends on the machine.
The Allen machine I have has a neon filled tube. It may have some xenon in it but it’s mostly neon.
And the way the light is triggered is different than a Sun machine.
Between those two things, the slew rate of the “timing light” on the Allen is small enough that it is faster than the electronics in these ignition boxes.
Because I’m pressed for time I grabbed a dual point distributor I had on the shelf and tested it. At 8k it had 1 crank degree of retard and at 10.5k it had another half crank degree of retard.
I grabbed my notes and I have tested a Unilite that was locked out and it had half a degree of retard at 9800 and it held that to 11k.
It’s worth pointing out that is far above the rpm most guys are running and quite a bit higher than most distributor machines can do.
I’m pretty sure that Marquette machines don’t go that high either. There was a company called King that made machines and those may go as high as the Allen but I can’t say for sure one way or the other.
I don’t have any notes on the Chrysler trigger so at some point I’ll test it.
With that in mind it seems clear that when using points or a Unilite to check for retard you can say that all the retard is in the box.
However, it would seem pointless to test an ignition box as a complete unit as it would run in the car and not use the distributor that will trigger it.
That’s akin to testing with a carb or header you won’t be using.
That’s why I stopped doing distributor curves if they don’t want to send me the entire ignition. At this point, I’m almost to where I’m not going to do any distributor tuning if I don’t have the engine on the dyno.
Interesting, Thanks for the results.
"Because I’m pressed for time I grabbed a dual point distributor I had on the shelf and tested it. At 8k it had 1 crank degree of retard and at 10.5k it had another half crank degree of retard.
I grabbed my notes and I have tested a Unilite that was locked out and it had half a degree of retard at 9800 and it held that to 11k."
"Because I’m pressed for time I grabbed a dual point distributor I had on the shelf and tested it. At 8k it had 1 crank degree of retard and at 10.5k it had another half crank degree of retard.
I grabbed my notes and I have tested a Unilite that was locked out and it had half a degree of retard at 9800 and it held that to 11k."
Unless you were testing to see the amount of timing retard the individual parts are contributing to the systems total amount of retard.
So far, single point, dual point and unilite distributors by themselves appear to contribute very little timing retard as a trigger for the distributor tester. I wonder how a chrysler distributor would compare?
I looked up a Mallory hifire 7 ignition and it looks like it can be triggered by points or a magnetic pick up. It would be interesting to compare the total system retard with the points distributor vs the chrysler magnetic pick up distributor used in the high rev 7500 test.
How does the Mallory hifire 7 trigger the distributor machine. does it use a tach output from the box?
Newbomb Turk
Well-Known Member
The box doesn’t trigger the machine. The machine has its own coil.
This machine functions differently than a Sun and the others I’ve mentioned, other than the King machine and I can’t find much on it.
The Sun machines were designed when points were it. This particular series of Allen Machines (22-250 and 22-260) were designed for electronic ignitions.
In fact, most of these early machines, the Allen included do not have RPM capabilities above 6000. This series of Allen machines can exceed that by 4000 plus RPM.
That doesn’t mean the Sun is wrong with what it shows. It’s just that the Sun and the Marquette and any other machine designed for points have been adapted to do electronic ignitions.
I can test ALL these distributors as stand alone parts. And what I’m telling you is that IF the distributor has SOME retard it’s far enough up the RPM scale that most guys would never need to account for it.
As I’ve said before, it’s the best option to test the ignition EXACTLY AS IT RUNS IN THE CAR WITH THE EXACT COMPONENTS USED IN THE CAR. That eliminates ALL other influences that can skew the results.
The simple fact is that ALL ignition boxes retard. Which was the point of all this, and why some guys can buy an ignition and lose power.
It’s not that the ignition is bad. It’s that they have never been EDUCATED on what exactly is happening and how to address it for maximum performance.
The Chrysler ignition gets an inordinate amount of misinformation (bordering on disinformation) because of the amount of retardant the later boxes have.
I suspect that the reason the later boxes retard more than the OE boxes did is due to the fact that once Chrysler (or any other Tier 1 manufacturer) stops using these parts at the base manufacturing level, the aftermarket gets to establish its own set of standards for components and the lowest bidder wins
Now the electronics are cheaper and slower so the boxes retard even more. And the people buying this stuff have no clue other than everyone calling them junk. When in fact they are not junk, they just require a different curve to account for the amount and timing of the retard.
You have yet to explain how the Chrysler Gold box I had would show 1 degree of retard at 10k. With a Chrysler magnetic trigger. Was it the box. The distributor? Some of both?
When you can tell me how many licks it takes to get to the center of a Tootsie Pop maybe we will find the answer.
I’m not a fully funded research facility that can spend the time and effort to chase down every degree. I also think it’s silly to believe that level of testing is required in these cases.
I know you want to jack up another thread with your ambiguity but it gets a bit senseless don’t you think?
Do you ever test any of this? It seems that you do not. You guess, speculate, equivocate and then move the goal posts.
Rather than test a bunch of **** I already have so you can continue to confuse the facts with bullshit, how about YOU fire up YOUR distributor machine and do the tests to prove me wrong?
No matter what my results, you will continue your grade school antics.
Just like the rocker arm flex thread, which you’ve done ZERO testing to prove your theory, I’ll wait for YOU to prove me wrong with YOUR testing.
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Newbomb Turk
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