H4Inf

ok we just tested this on the bench, but have a few queries.

Question 1:
Since we're testing on the bench we don't have the ignitor's signal to tell the circuit to fire the coil. Is it okay to say tap a voltage source thru the wires that are supposed to run to the ignitor on the dizzy? How many volts? We have tried with 5 and 12, tapping, both seem to work, but not 100% spark rate for the tapping. What is the correct voltage?
EDIT: Just read Kent's email - meant to tap ground! Ahhh. brb testing

Question 2:
Would it make any difference having only one spark plug plugged into the dual-output coil, instead of 2? Currently we have only one connected.

Question 3:
Will there be a visible difference on the spark plug (in daylight) indicating spark strength? Or do we need to test this on the car to be able to tell the difference?

Another thing we noticed, the red led (ignition pulse indicator) did not seem to be flashing at all.

Cheers

Paul & Rob

gsl-se addict

iTrader: (3)

1. Yep, tap against ground. That is what the ignitor does. It pulls the C terminal to ground when firing.

2. It is best to have both the outputs the same. Siince it is a dual output post coil, the spark will want to take the path of least resistance. You woule like to have them be nearly the same.

When I tested, I had it like this:
-12v to tan wire on coil (I used a 4amp capacity PS, but a battery would be better).
-ground the base of the coil
- output from TT goes to red wire on coil

You can ground the base of the plugs as well. I left mine ungrounded. In my case, the spark shoots through both center electrodes to the outter electrodes. The spaark would then jump from the side of one plug to the other.

I found that taping the input rapidly seemed to work better. I ended up building a square wave pulse generator with simple parts. This way I could have it fire over a wide range of values of RPM. The spark is much more consistent this way.

3. The sparks should be long and intense. Make sure the connections are good and your power supply can support the current needs of the coil.

For the LED, you may not see it. This is because the max pulse limiting limits to 4ms. You will probably see it better in the car. Also, The LED could be in backwards causing it not to work.

Let me know if you need anything.

Kent

H4Inf

Fantastic! We did a series of tests today in progression.

1. We setup everything on the bench, ran 12v from the car battery and tapped on ground. It worked

2. Next we connected the trigger of the circuit to the ignitor in the car, and ran the car on the stock setup, however with the TT&2nd gen coil running as well, on the bench. This was to test that the circuit was recieving the trigger and actually firing the plugs. This was successful

3. We temp-mounted the coil and box under the bonnet, and connected leading plugs to the 2nd gen dual-output coil. After working out my ECU wasn't getting the ignition signal and hooking that up, it started and ran fine I just need to mark TDC on the pulley as the mark is long gone, and get a fusebox to replace fusible links, so I can mount the 2nd gen coil there.

After testing that it ran, we removed everything as we are going to design a neater way of setting it up, and design some good mounts to take the heat away from the coil as well. One thing I noticed was that the connectors for spark plug leads on the 2nd gen coil are larger than the normal ones, and my wires keep popping off!!! There must be special ones to get for this?

It was a little trickier than usual as I have an aftermarket ECU, but after we figured that all out it was sweet No notes on performance yet - I also have to work out why my dizzy is impossible to move by hand (advance/retard timing) - even having removed the bolt - it will only budge with a heavy mallet, and refused to loosen up.

Thanks for the help Kent We will keep you posted.

gsl-se addict

iTrader: (3)

Good deal. Nice to hear. Do you know what resistor Rob used for the max pulse? Also his IC uses a shorter pulse than mine using the same resistors/capacitors. Mine the output is tx=Rx*Cx, his is tx=0.7Rx*Cx. Just trying to figure out what you guys are running.

With the spark plug wires, are you using 2nd gen ones? The 1st gen will work in the 2nd gen posts, but they are real tight and hard to get in all the way. You can also switch to 2nd gen plugs on the leading with this setup.

Could you see the output LED with it running connected to the car? Also, could you test/feel the back side of the coil when testing. I am trying to determine what the best value for the max pulse should be. I expect the back to get pretty warm, but hopefully not real hot.

Let me know if you guys have any questions. Good luck with the further testing.

Kent

H4Inf

Hi Kent,

With the ST M74HC221B1:
MIN: Rx = 2.2/0.07= 31.43 (33kOhm)
MAX: Rx = 3.9/0.07= 55.7 (56kOhm)

I'm using first gen spark plug cables. I noticed they arent long enough, and mine are new so the plastic surround is causing them to pop off - I had to tape them on during testing.

I remember being able to see a very dim light from the output LED, it is similar to my ECU's led's once you rev it up it is either dim or just looks on. The power led was pulsating a bit too.

With the 2nd gen coil, the back did get warm, but not really too hot. I revved the car only to about 4000 rpm as it wasnt warmed up.

One thing we noticed when we tested only with a single spark plug on the dual output coil was some arcing from the unconnected post to the one with the plug on it. This produced a much louder sound than the spark plugs produced.

Paul.

gsl-se addict

iTrader: (3)

Okay. Sounds good. Some 2nd gen plug wires would work well with this setup. My wires were real hard to get on all the way. I had to measure resistance from one plug wire to the other to make sure they were plugged in all the way. You may be able to get some custom or universal wires that would be about the right length with the correct ends.

I think this limiting should really help with ignitor life. I think the J-109 puts out something like 6.5ms pulses. If you have an o-scope, you could test to find out. With constant 2.2ms tested before, the low end was a bit week. I figure around 4ms should be a good compromise. We could go a little lower or higher depending on performance vs. temperature of the coil pack.

H4Inf

Cool. I can get an oscilloscope in a couple of weeks to do some testing, and will get some dyno results soon too

Just wondering what plugs do 2nd gens use. I am using NGK BR8EQ's - 4 of them, which each have 4 prongs, as seen in the image of the previous post. Just wondering what the difference is with 2nd gen plugs?

gsl-se addict

iTrader: (3)

The 2nd gen leading plugs are BUR7EQ. Instead of having 3 or 4 side electrodes, they have a ring that goes around the outside acting as an electrode. This allows the spark to jump to any point. These are commonly called surface discharge plugs. They look like this (2nd plug from the right):

H4Inf

Cool cool Just need to figure out why my dizzy is stuck solid, get some plugs, leads and mount I'm thinking of perhaps setting up a switch to just switch between 1st gen and 2nd gen ignition systems - of course having to manually switch leads and adjust the timing.

Also, as you said the timing will need to be advanced due to delay with the coil, does this mean I'm meant to line up the dot on the pulley with the mark, or do I need a new dot for this system?

Thanks

Paul.

gsl-se addict

iTrader: (3)

What you can do is use a new ignitor connector on the TT. Leave power connected to the old coil. Carry the 1st gen plug wires with you. To switch back to stock, unplug the TT connector, plug in the 1st gen connector, reconnect plug wires and you are set. The timing will be a bit off, but that's okay. I can switch back to stock in less than 5 minutes with the way it's connected.

The timing is retarded with the TT. This means that if you had the marks lined up on the stock system, then connected the TT, you will find that the mark is about 8* retarded. All you have to do is readjust the dizzy to get the mark lined up again. Even with the timing retarded, I noticed a big gain over stock. Advancing the timing back, just makes it better.

H4Inf

awesome stuff! can't wait til next weekend to get it sorted now thanks for all your help. once Rob gets his car back I think we will be installing the TT for his too, and we'll put together a pictorial writeup of how it all goes together... and ill try to get onto setting up a website for it heh.

H4Inf

it is now next weekend, and its not going so smoothely.

Symptoms:
Start engine, it runs, but really rough and bad, not nice at all. Leading plugs are both firing - confirmed with plugs and timing light on both front and rear.
Tacho does not work!! if that means anything?

Need confirmation of which ignitor is for LEADING.. is it the one on the left of the dizzy (towards radiator), or the one on top of the dizzy (under alternator).

Any suggestions would be great, its getting late and we just want it to work!!!! like last time! --

I have completely disconnected the power from the 1st gen leading coil now, there is only one wire connecting to the - (trigger) of it now. This measures 0 resistance to the plug which I have unplugged from what i believe to be the leading ignitor (on left of dizzy).

tips, thoughts etc. would be top!

cheers

Paul

gsl-se addict

iTrader: (3)

Hey Paul,

The ignitor on the front shoulkd be leading (closest to rad). The one next to the alt is the trailing. Norfmally, the North American cars get the tach froim the trailing coil. Yours may be different as cars in Aus keep using the thermal reactor for these years, correct? The 79/80 (used thermal reactor) in North America attached the tach to the leading because the trailing only fired part-time.

Do they timing marks line up when it is running?

Few things to check:
- 2nd gen coil mount needs to be grounded. It normally gets grond through the mounting bolts, but you may want to run a separate ground wire.

- The leading ignitor (closest to the front of the car) should see about 12v on both terminals with the key on and not running. The top one (horizontal one looking at the plug) should be a bit lower on the voltage than the other one.

-Does your ECU get the tach from the trailing?

-Make sure plug wires are connected well.

You do have power to the ignitor (1st gen), right? The bottom terminal should to connected to battery (either black w/ white stripe or black w/ yellow stripe wire stock).

You can also do some checking on the circuit. The circuit should have the following resistances (when unplugged)

- 12v to ground ~6kOhms (I think)
- 12v to input (C terminal) 1kOhm
- output to ground 1kOhm

Good luck. Let me know if you need help.

Kent

H4Inf

hi Kent,

Rob and I are totally exhausted... although Rob is now building the simple circuit tonight and we will see if that works any different tomorrow..

Basically today we pulled out my dizzy and lubricated it, as it had coroded and became stuck, put it back in, started up on stock ignition - no probs all still good (i took note of the position of the shaft etc. to make sure it went back in the same way). all good.

now when we run the TT setup on its own, the car runs really rough, whether i have trailings plugged in or not. just not smooth at all, very rough! not sure why yet.. as i said its late and we have been working at this all day. Now heres the weird thing. When we run both the stock system and the TT together (Stock system firing plugs on the bench, TT running engine), it runs better.. not sure why yet.

To my stock leading coil there are a few connections:
+ --- ECU power & 12 Volts from ignition switch
- (trigger) --- ECU ignition pulse & wire which has 0 resistance to the terminal going to the leading ignitor. (now when this wire is unplugged, the tacho doesnt work - so i am presuming tacho is running off leading coil, but has been spliced into this wire somewhere.)

I'm finding it hard to see the difference between running both systems at once and the TT alone. My non standard ECU provides fuel, and is recieving the rpm signal (can read it on the handset - even when tacho is not operating) - and the ignition should be run by the circuit..

its late and i dont think i can think straight any more heh.

so to answer your Questions simply:
- rob put a 2nd 12v connector to the circuit, which runs out to power the ignitor
- ecu gets tach signal from leading coil trigger
- plug wires have been zip-tied to the coilpack and we have confirmed spark from the system with plugs on the bench and a timing light on both leads

We will go over it again tomorrow and hopefully solve this. My car came in a bit of a messed up wiring condition lol, so there are a lot of wires which change colour all the time and its just confusing to say the least. Lots of work to do hehe

Cheers

Paul.

H4Inf

oh yes and we tested resistance from the coilpack base to the battery negative. 0. so thats fine.

we also made up some layered aluminium between the coilpack and the mount to help transfer heat away from the pack itself.

H4Inf

OK Sundays news.

We found TDC and marked it on the pulley. The stock timing was dead on 5deg before TDC as it should be.

Next we setup the latest version of the TT circuit (modified to suit locally available components). We have a few interesting unexpected things to report on:
- Timing was retarded by about 35 degrees
- We pulled the dizzy and advanced it a tooth and set the timing to about 5deg BTDC
- Noted that the timing wasnt stable/smooth. At idle and higher rpm's the timing mark was not appearing still as it does with the stock setup, it was jumping back and fourth a little bit - perhaps up to 5 degrees.. sort of slack in the timing.
- Upon increasing revs, the timing actually retarded instead of advanced!

Second Attempt: We setup the original simplest TT circuit as in the writeup.
- Timing was retarded but not nearly as much with the newest circuit
- The coilpack heated up rapidly, and as it got hotter, the spark was cutting out - missing. We could see this with the timing light on the lead. So when we first started the car and the coil was cool, the spark was reliable, but just sitting at idle for about 2 minutes, spark became less reliable, engine started to stumble
- Mechanical dizzy advance seemed to operate normally as stock, so as rpms rise, timing advanced as usual
- Again, timing wasnt smooth/stable (however it was better than the latest circuit) - jumping back and fourth about 3 degrees at any rpm.. (with stock setup it is perfectly smooth without fail)

We tried 2 coil packs for both of these setups, with no change of behaviour in either.

Our thoughts::
- Perhaps the latest circuit Rob built had some heat damage to some of the components causing this timing retarding with increased rpm.
- The simple circuit is beyond doubt in perfect working order, using exact components as specified - this can't account for the jumping in the timing. I understand that at the low rpm the pulsewidth is going to be huge, which is why the coil gets so hot. Could it be possible that electronic interference is being recieved by the components?

Should this mod be more significantly seen on the carbied car than an EFI car?

Any light on our situation would be great!~

Cheers,

Paul.

gsl-se addict

iTrader: (3)

Very strange stuff. I spent Saturday modeling the new circuit with Electronics Workbench. It appears to work just the way it is suppose to. Prior to this, the new circuit mods were just figured out on paper. I checked everything several times to be sure all was correct.

Now, if you have access to a function generator and an O-scope, you can fully test was each circuit is doing. This is what I am thinking:

- On the lastest design, some of the components are static sensitive. One of the components could have received a static shock during assembly causing the strange behavior.

- What I think may be more likely is that the timing chip is set to trigger on the falling edge instead of the leading edge. The inputs are different than the circuit I used. I am pretty sure I told Rob the correct pins to use based on the data sheet I have on the IC, though. The triggering thing can become confusing, so who knows. Having this wrong would make it spark opposite to when it is supposed to. Definitly could mess up timing and such.

- On the simple TT, that is pretty strange as well. The simple circuit just inverts the singnal and limits it to 5v. It seems if things are stable with the stock, they would be with this TT as well. Sometimes timing lights behave strange with direct fire systems. This is becuase the plugs are firing twice as fast.

My car is EFI and had no issues with the simple or fixed pulsewidth circuits. I never got to try the autoswitching versions. I did fully test the previous autoswticher with a scope and function generator. It worked just like it is suppose to. Others have used the various versions of the TT on EFI cars without issue. I am not sure what is going on in your case.

Let me know if you guys need anything. I will have the circuit boards probably this week. Maybe I can put a board together for you guys to test. That should eliminate to possiblility of wrong componets, different pin connections, and so on messing things up.

Kent

H4Inf

Hey Kent,

it is an odd problem, for the advance to be going in reverse it is quite weird lol.

Robert just suggested to me before that perhaps the timing is not bouncing back and fourth - but the timing light is showing the dual pulses (as there are twice as many sparks from the leading now right).. ? So it will be showing when rotor1 and rotor 2 are firing thru the one light..

Rob's going to post up his ideas after tea.

Could there be any electrical interference problems? I think we may get some of your boards and bits!

Cheers,

Paul.

jimrs

Hey Kent,
Can you please post everyone that gets a completed "Gadget"
(rubbing hands together) i totally can't wait for mine.
and i hope that i am still on the list

gsl-se addict

iTrader: (3)

Jim,

I can probably do that. Didn't you order one on rotaryx? I am sure you are on the list. Even if you weren't, have have extra parts anyway. I will check tonight on the list. If I post the list, it will be in the GB interest section. Anyone worried that they are not on the list or those who want to be added to the list, go ahead and contact me.

I am going to ship the Australian guys a couple kits tonight so they get start doing some more testing. I am assembling and kitting the other circuits. Waiting on the connectors and wire before I can start packing and shipping the others.

Kent

jimrs

Kent,
Thanks, yes i did place and order at rotaryx,.....i just wanted to make sure.
Also i am very anxious,...to say the least.
Just awesome that you are doing this, i can't thank you enough.....also makes for some great reading.
thanks
Jim

riceburner1r2001

iTrader: (4)

hey my car want starting and weird thing. i took out the L2 from the 2g coil pack and it started, could the coil be bad from the 2g coil

riceburner1r2001

iTrader: (4)

also i am getting spark from both plugs plugged into the coil, but when i 1st took out the bottom 1 and had it barely hook up it started

riceburner1r2001

iTrader: (4)

here u go

gsl-se addict

iTrader: (3)

More details, please. What version of the TT are you using? I am not sure if I understand the problem. Are you saying that it won't start if you have both plugs connected? Or are you just surprised that it would run with only L1 connected?