Ive got a few (like 15) VW/ Audi ignition coils layin around and im thinkin about wiring them in to try and eleminate possible secondary ignition problems, instead of buying stuff, and besides the other benefits.

I cant really find any info about using or not using this method other than the floppy end is made to sit stationary in a valve cover. It doesnt seem to dificult to make a mount.

D/ term. 1 of coil is fused switched power. 2 & 4= ground. Im thinkin pickup wires would go to 3 & 4. Or would one wire be power to pickup and other go to term. 3 in place of ecm signal?

Any thoughts on making this a usable setup? Or am I retarded?

 

Most of the COP setups use a fairly long tower to reach from the coil all the way down to the plug. Packaging and mounting that setup on a rotary engine is usually more of a PITA than the elimination of the plug wire is worth.

The second issue is the energy level available through COP setups. Compare the mJ rating for the COP coil and a good standalone coil. You'll probably find that the standalone coil is superior.

 

Thanks for the advise.

If it becomes a PITA, I probly wont use it long term. But for testing purposes, would the pickup need its own power wire? If not what are your thoughts on where the two pickup wires should go?

 

Only "why not" issues I can think of would be mounting concerns, and maybe heat if you mount them too close.

I'd miss the ease of changing plugs that comes with the standard setup, myself.

 

Well I cant get theese coils to fire with the pickup, but with power and groung on 1 &2, applied voltage on 3, gets spark. Pickup hooked to 3 and 4 either way, nothing. Any ideas?

Ill worry about mounting, heat and access to plugs if they will even work.

 

Judging from the diagram, the coils have the equivalent of only the final stage of an ignitor built into them... but we don't have specs on the trigger condition.

Looks like 2& 4 should be grounded, 1 is +12V supply current via a fuse, and 3 is the trigger. Hard to see from the picture, but the "ignitor" looks to be an NPN transistor, in which case the trigger lead (also known as the "base") requires a specific positive current (not just positive voltage) to trigger reliably without hurting it.

If you don't limit the current into it, it'll eventually melt down. But without specs, there 's no way to be sure what that current limitation should be. It's built into the ECU in the original design.

If you had access to a working car from which these came, you could measure the trigger current. Or if you have spec numbers on the component, you might be able to research the rated current. Or you can experiment, starting with like a 1k resistor, and see how things go.

To go from a 1st-gen (81-85) dizzy to this unit, there needs to be an amplification stage between the pickup coil and the input of the COP. Might be able to trick part of an ignitor into doing it, minus the final output stage.

 

Ya, I tried using an ignitor and nothing happened. Might just have to go with the standard ford or G2 coil setup like everyone else. Guess thats why they do it.

 

I'm with DD on the inputs, but you probably need some sort of positive
going square wave to trigger the coil to dump the primary to make spark.
You'd have to find out what the current input specs might be. Try looking
in the megasquirt sites as someone may have documented how to drive
it with a MS box and that might help you out.

When I did my TFIDFIS ignition (see link in sig), the megasquirt sites helped
me under stand it really well. You might be able to use the tach output
generated by a 7 pin 5+2 HEI module to drive those coils, I'm not sure
because we don't what the specs are for that input.

 

That's because the normal ignitor design is an interrupter of coil current, just like the transistor inside your coil pack. the ignitor doesn't output a current, it interrupts the current flowing thru the coil. When the coil primary's magnetic field collapses, that's what generate the spark high voltage in the secondary coil. Kind of like releasing a spring.

You could probably rig an ignitor to do it, but you'd need more components on the output side of the ignitor to develop the proper voltage and current for the trigger.

I understand that the J-109's can be disassembled (never used them; my '80 has J-105's - very different electronics); you might be able to tap off the amplifier stage before the final output transistor, and it might do what you need. But it would require some skill in component-level electronics.

 

t g farrel, ive read your write up, very nice. After reading it i started to wonder if i could make theese work but theres alot more involved than i thought. Might just go that way, sounds alot less complicated. Ive seen some vw guys that do newer 1.8t swaps in older cars and they dont even run stock coils with ms. Must be the reason right here. Thought id give it a try though.

Thanks for the info DD. I think ill settle for a system that is known to work well. Unless I feel like spending alot of time setting up a new, probably more complicated one, to get the same results.

Thanks guys!

 

Its not current that drives a transistor its voltage. .6 volts or more is what bias's them on the base. So you unbias it. Ground if you want, Transistor goes from saturation to cut off. Looking at the diagram, If you were to get a O scope it would look like a square wave. Its just a on off from the CPU to triger the Coil. You would need a sine wave to DC converter like that of a GM hei ignitor to work. You may be able to use the Stockers to trigger this idk. You would have to do some bench testing. If i had a pair of these a audi car to hook a oscope to i could help to figure this out.

 

What part of Oregon you from? I grew up in Florence. Im here In maryland for da military

 

Cool, I grew up in the Salem area, but im livin in Hood River now. I cant wait to go back to Florence and ride! I went basically the first nice weekend a month or two ago, its just too far of a drive to do as often as id like. Maby in a month or so. Lots of trails where im at now though.

So would you need a scope to verify the audi/ vw pattern? Ive got a scope at work, and theres always on of the two makes there, all tdi right now though. Is the rx7 pickup too weak of a signal or is the A/C unusable with theese newer parts? Cant a diode sort of convert/ filter to a usable D/C signal? Well I guess it would not be square anyway. Nevermind, just kinda answered my own questions.

Is this why most people use the gm hei ignitor, to convert A/C sine wave to D/C square? What does the stock ignitor do with the sine wave? Sorry for all the questions, and thanks for the help.

 

Same thing, Ac to DC converter. But the GM hei is able to handle more power. I havnt been on the dunes in about three years now In High School i had a 2wd nissan pickup that had some tires off a tahoe and thats what i used to have some fun

 

I am shamed to have been caught out wrong. Way too many years since I did component level stuff, thanks for the correction.

V is right; standard linear transistor uses a bias voltage to control a current. Dur.

 

Its all good, Just trying to help.

 

Cool. Thanks for the info guys. Ill update if I feel like going into this project.

Cars/ trucks in the sand sounds fun!! Ill stick with my bike though.