From what I remember, if you rip open the Miata's harness a few inches back from the coil connectors, it used a #12 or #14 (Blue). In no way was it a #16 or #18 feeding the factory coils. I'll have to go look now. I may have used a #14 for power and ground in the cop harness. =)

The AWG table posted above states:

#18 - 2.3a - 6.385ohm/1000ft
#16 - 3.7a - 4.016ohm/1000ft
#14 - 5.9a - 2.525ohm/1000ft
#12 - 9.3a - 1.588ohm/1000ft

Their description of chassis wiring is: "Chassis Wiring is also a conservative rating, but is meant for wiring in air, and not in a bundle."

I can see at high RPM one of these coils pulling ~2a easy. x4 = ~8amps. A #18 is clearly undersized in this example. If I have time I'll test a coil at '8000rpm' and see what it pulls. I will account for compression as well. (66hz sequential or 132hz wasted spark)

Anyone ever look at a s2000 COP to see if it has the right dimensions and inputs/dwells are reasonable for hooking up to a Miata?

Most of the cop coils with an internal ignitor will have similar dwell so they could work. May not as common as the Toyotas. Do other Hondas besides the s2000 coils use the s2000's engine? The Toyota 1ZZFE is found in '00-'06 Toyota Celica GT, Corolla, MR2, Matrix, Pontiac Vibe and probably others.

Not sure about what might else use the engine. Someone asked me about it and I figured this was the place to ask before trying to dig up some tech specs on the COPs (no luck with google yet). The Toyota coils make sense for a lot of reasons.

Score

Loews had a metal strap 1.5 inches wide and 22 inches long. I'm gonna cut it down and use it for my COP bracket. It should turn out better then the 22 gauge metal sheet I got from home depot. Ill post pics tomorrow of the outcome.

http://i27.tinypic.com/28uqmh.jpg

It's only a matter of time before the handcream jokes start rolling in.

For what it's worth. s2000 coils are:

Pin 1 - Trigger
Pin 2 - Ground
Pin 3 - Power

There isn't a tach output.

All 4 coils are fed V+ through a 15amp fuse.

Yea, saw that after I posted. I have really dry hands ;)

Result:

http://i25.tinypic.com/14nskk.jpg

Cost = $5 with nuts and bolts.

That #4 coil should line up with the valve cover bolt ?? I just used a spacer and a longer bolt on mine.

yeah - I did the same with mine - it lines up well enough. 75 mm bolt I think, and it was a slam dunk, with a short spacer.

Today I got a coil (two) in the mail which I bought as spares, but they have a different angle. The hole is straight off the back of the coil (though offset slightly) instead of on the side. Functionally the same I imagine, but a different packaging. Pretty interesting, I don't know what thye are off of, but they look identical to the other COP from toyota aside form it. Pics if people want them tomorrow.

Pics and part number. There are at least 4 different part numbers for Toyota cop coils. I haven't seen a side by side comparison yet to know the difference.

its the same coils for corolla, celica, MRS, Matrix...same motor in all
the coils are app specific due to those mounting holes only...

I didnt want to disturb the valve cover bolts. I figured they are there to hold it down and a longer bolt wouldnt let me secure it well enough. Besides, I doubt whoever looks under my hood is gonna go "nice turbo, oh and one of your coils isnt straight".

Sam, what's your strategy for the wiring harness?

I got the toyota connectors on the way, I got braineacks letter with the contacts and I have weatherpack plugs sitting on my desk.

Its the more expensive approach but I do it once and do it right.

I also got bored tonight and painted my bracket.
http://i27.tinypic.com/9igvf9.jpg

'straight style' 90080-19023 coils
 

"one" of mine isn't straight. They all are the same. It works out well. I just drilled and tapped the plate so it sits flush, instead of needing nuts or screws from the back or anything. I just twirl out a 10mm cam-cap bolt and the coils come off. Except the one in the back, I used the longer bolt and a spacer, and it's probably the best held down part of the entire valve cover.
http://abefm.smugmug.com/photos/258959385_UphCw-L.jpg
http://abefm.smugmug.com/photos/258959336_SctEu-L.jpg
http://abefm.smugmug.com/photos/258959423_HETZX-L.jpg

And this is the "regular" style on my car, as installed now:
http://abefm.smugmug.com/photos/258961640_RqsoE-L-0.jpg
http://abefm.smugmug.com/photos/258961724_9V2mm-L-0.jpg

To do it the way I did, the tolerances on where you drill the holes are relatively tight, but not unmanagable.

If I had 4 of this "new" straight coil, I would have all the bolts in the front, and the plugs in the rear, I think it would look good.

So you are going to install a weatherpack connector before the factory coil harnesses and then install 2 mating connectors (factory coils and COPs) so that you can swap between the 2?

Exactly. So if we could gather each part number and pics of the corresponding coils it could be beneficial to have that all sorted out. The '01 valve cover I'll be using might be better off with straights, or maybe angled? I don't know yet. There's alot of crap in my way on that valve cover that limits where I can weld on bungs.

i think the collection of part numbers has already been started in the sticky version of the COPs how-to
mine are angled, and the part number is already listed, so people with the less commong COPs need to step up and list their part numbers so we can differentiate

Yes. I am going to chop off the factory harness and put a weather pack on it, the factory coils, and the COP's. I will pull the factory coils out though, I just wanted the ability to swap between them quickly if I ever have too.

Hey Abe, question. Did you JBWeld nuts under your plate so the bolts have something to thread into?

I just fired up my COP conversion for the first time. OE ECU, 01 Celica GT coils, new Toyota connectors, and harness connectors hacked off the back of my dead OE coils. Started immediately, good tach signal, nice even idle.

I did the mounting a little differently. I used some aluminum U-channel we had lying around, plus a bracket made from .125" aluminum flat stock. The bracket bolts to the center valve cover bolt, then the U-channel is held onto the the bracket using a 10mm nut and bolt. There's nothing to keep the packs from rotating, other than the pressure from the U-channel, which is enough that they can't be moved by hand when snugged down.

Great writeup, thanks all!

Nice, I like the bar - I almost did something like that myself. Heck, you could use wing nuts to keep the coilpacks "hand removable", like in a normal car. :-)

No, I tapped the plate with a $2 tap from my FLAPS. I was worried it would be too thin, but it worked out. It's only a thread or two deep, but it works better than I would have expected. So my plate is flat on bottom up to my ability to cut my bolts to the right length.

looks good, this thread has helped out a lot.

Thats pretty smart.

Mine sits flush as well, I just used a drill bit almost the same diameter as my flat head bolts and they tucked into the bracket.

Uh huh, that was Braineak's claim as well. I'm sure it's fine, too, since there IS a gap down there. But what I don't like about it is that (it seems? Correct me if I'm wrong) to get the coils off you have to pull the plate, since there's nothing to keep the flatheads from turning.

Anyway, for all the care I put into making it, I did it upside down so my plate sticks past the back of the engine and has a gap at the front. I would concider doing a bar on the top next time, though I'm happy with what I got.

Actually, maybe I'll look at just tapping the valve cover itself next time. It's thicker, clean, and already there. I wonder if it would leak?

That is what I plan to do.. Probably just put a little loctite blue on the threads to act as a sealant.

you wouldn't have to drill all the way through the valve cover - you could in fact drill part way down, tap, and thread a stud. that would leave you the opportunity to use a wing-nut on top of the coil for that easy-to-remove juicy goodness.

It's thick, but not THAT thick. You'd be lucky to get two threads in. Still, I like the idea. The easiest thing to do would be to put a nut on the outside to lock it on, but if you have big nuts (pardon the pun) you could put a nut on the backside to hold it in.

Or a partially threaded rod. Ooooooo.... I need a lathe. Then it would go in like a bolt, and you could put a wingnut on top.

But practically, my 10mm nut driver works great.

Interesting enough you're idea is probably simpler then mocking up a bracket. Just mark the holes for the studs with a hammer and a nail, drill and tap. Granted, that is if you don't have to pull the valve cover to get the shavings.

Slick idea, but I don't think id go that route. I prefer reversibility.

I don't have to pull the plate to get my cops off and my studs dont turn either. I used a nut to secure the bolt(stud) to the plate. Put some loctite on it too, its never going to turn.

http://x024.uploaderx.net/x/172_1203896833.jpg

I drilled and tapped an 1/8" aluminum plate. Used JB Weld on the threads and the backside of the plate.

some of you people over thing this shit too much. :)

My cops bring all the boys to the yard.

Btw. Watch for a thread in the next few days for an interesting announcement if all goes as I plan.

I see a few that'll work. Have a good day at the junkyard?

Curious to see that one. I know at least a few of those are high current switched, not 'triggered' ones like everyone is so fond of....

converting your dual plug 16 cylinder to COP?

Nooooooooooo ;)

I used threaded rod tapped into a spare valve cover. a nut on the topside locks the rod in place. Topped off with some dome capped nuts, makes it look like the rest of the valve cover ones.

Pics to follow soon.

Cheers
Nuno

I bought a spare 96/97 engine harness to see what it would take to make a plug and play COPs setup from the square 4 pin connector. After removing the tape to separate it from the injector harness it looks like it'll work real well. The only minor thing is that it sources ground after the connector.

http://i154.photobucket.com/albums/s...6/IMG_0696.jpg

Orion, I didn't realize that the square plug was actually the other end of the 2 coilplugs. This really simplifies the COP harness in my mind. Thanks.

Well there goes all the engine harnesses for Miatas. lol

yeah, I want to see this!!

that does look like it will simplify it a bit, im not doing it though, ill stick with what i have already
this, i would say, is a very good alternative to the guy who doesnt have a bunch of dead coils like i did to make a harness out of

Interesting. I thought blue was hot only in ACC and RUN, not Crank.

Ya. I was expecting white/black for power given what's in the 97 wiring diagrams. The other end of the 4 pin connector in my car has a white/black wire.

FYI Guys. Since I dont have a dremel I couldnt do the mod to the contacts that Braineack recommends in the archive. Chad recommended I just hack saw the end and bend the contacts down. It was simpler then that, I hack sawed and the contact just crumbled away. Hacking away just what is pictured made a perfect fit in the factory connectors.

What's the part number on the connector to the coil pack?

4k update
 

Have almost 4k on the coils now. Interesting update.
Lately it's also not really had the pull I expected at 10+ psi, but mentally I attributed it to the shitty gas blend we got this winter, and my subsequent reduction of timing in boost. Yesterday I entered an illegal contest of speed, and got some misfires at higher boost. Ignition break up at high load is almost always spark plugs, so I picked up a new set on my way home.

Went to intall the new plugs after dinner. Pulled the old ones out, and the business end of them looked perfect, great color, square and straight electrodes. But the top end that meets the coil was fouled with black deposits. I pulled them out and cleaned them with a wire brush on a cordless and put them back in. Car takes off like a rocket again through 15 psi.

A co-worker of mine said he's noticed the same thing with his Toyo coils, and cleans the tops of his plugs periodically.

Are you using dielectric grease?

Not previously, but from now on.

great update Ben, safe to say its a must from now on for everyone...i never used it before, but sure will now

Jason, any updates on your project to correct the dwell?

Is it arking to the top of the plug? You don't suppose one of the springs in the cop is missing or squished do you? I forgot if I ever mentioned that I filed the edges of the round plastic area of the cop just above the rubber seal. It was touching the 'cam humps' of my valve cover. Do you have a caliper to measure the plug depth and verify it's making contact?

https://www.miataturbo.net/forum/sho...t=toyota+dwell

bam.

I was actually looking for updates on a circuit he is building for those running stock ECUs that cannot adjust dwell times. I have a 99, and don't want to burn out the Toyota COPs.

Thanks,

Jason

oh my bad i missed the "correct the" in you request. i blame beers.

This is bullshit. I put in my coils yesterday, wired them up as per the archive thread. Try to fire it up and nothing. Just floods. I started with my working MSQ and only changed the dwell and it didnt start. Then I tried fiddling with the dwell settings, crank settings, ASE settings and nothing helps. It sounds like its about to finally start and doesnt. I get spark on all four coils as well. At this point I am waiting to get my other set of weatherpacks to wire the factory coils back in and see what happens. This is really upsetting me and I have no idea what else to try.

Triggers reversed?

Cranking PW's too high.

I started the car flawlessly with new spark plugs and the old coils, let the engine warm up to operating temperature, swapped the toyota COPS back in and it started on the first shot.

I think it has to do with the fact that the COP's require much lower cranking PW's then the factory coils.

Its funny, but I would think with their more powerful spark the car would start even faster with the additional fuel required for the factory coils.

Anyway, I cut down all the PW's by 2ms in the 80-60-40 range and ill see tomorrow what happens.

Edit: Arkmage experienced the same starting problems I did when he switched over to COP's. I just remembered. I gotta see what cranking PW's he settled on.

Oh and the dwell settings def play a big role in the warmth of the coils. running 4.0 vs 2.5 was a big difference to the touch, ON A HOT ENGINE.

edit 2: I did learn something great from this whole ordeal. I changed my spark plugs for the first time ever,I was scared shitless the whole time but Chad was holding my hand.

What do you guys do with your wire coming off the COP's?

I wrapped mine in electrical tape, and its ok, but I wish it looked a little bit better.

Oh, and did you guys wind up changing your Cranking PW's after changing over to COP's?

I don't know wtf a cranking PW is. lol. Is that a MS thing? Is PW pulse width? What is the pulse width when the engine is running? Set it to that. I would imagine it's the same as your dwell. I don't think I have that in the ems.

I wrapped my wires in electrical tape. It almost looks oem. You could toss some split loom tubing over it. Maybe you could cut notches in the mounting plate and hide the harness under it. =)