Thanks Aidan, I agree with you. For reference, I've been watching this video: ; reading this thread: https://www.miataturbo.net/diy-turbo...-thread-82744/ ; and this thread: https://www.miataturbo.net/adaptroni...1/#post1005789

Are there any other or better references that I could use that you may be aware of?

:flame suit on:

Hey ya'll just wanted to offer an update. The NAPA ECHLIN IC413 coils are made in Poland. But that doesn't matter because my misfire issues where from hamfisting my plug wires. They are tender at the 90° and where breaking/broken apart.

Escalade wires work well in a bind, haven't had a misfire issue since.

My next issue is possibly fuel and airflow related. But i'll take that offline in another thread.


Moral of the story:
Check your wires
And still, just get GM Take off's or OEM Delphi over other.

Buy these ends from Summit and be done with your troubles. I used them on stock Miata wires to go to my truck coils.

https://www.miataturbo.net/attachmen...ine=1417095884

I use the stock wires but used the Taylor ends from Summit Racing on the coil side and shortened the high tension leads to match my needs.

https://www.miataturbo.net/attachmen...ine=1417133330


https://www.summitracing.com/parts/tay-46069

45s don't look as good with our style of bracket.

So get 90's?

That's what we had. But the 90* ends that magnecore suggested broke for both payam and I. You need to have a gentle touch with them. Which is why we are working on replacements.

Quick question in regards to wiring.

OEM has a 12v and ground going to each coil. Do I wire both 12v (black/white) wires to the pink wire and both ground (black) wires to the brown wire. Or is only one 12v and ground source sufficient for all coils.

Are you sure the power wires are thick enough???
 

Are the "Black/white" factory power wires a large enough gauge to supply current for the D585 truck coils? It seems awfully small for the whack these coils are supposed to give out. I just can't imagine a GM truck having wire that small driving 4 of its coils in its factory loom. Has anyone ever wondered about this?

exactly what i was looking for

:likecat:

Hey folks, I'm building a harness for my D585 coils and I wanted to pickup some capacitors. Last time I built a harness I picked up parts from my local RadioShack but as we know they're not really around anymore. Anyone have a suggested vendor for stuff like that?

I though most people were omitting the capacitors these days?

I tend to buy electronic components online these days from Element14 or RS Components but due to S&H costs prefer to wait until I've got a few things I need - paying more for S&H than the goods themselves just doesn't seem right. I usually end up ordering 10x what I actually need too (eg, rather than 1 trim-pot, I get 10 since they're cheap enough)

Yeah, hard to not buy in bulk for components like those with the cost of the shipping. If that's the case I will run without the caps, I know it was suggested pretty heavily when I built my COP harness but they're kind of in the way so not adding them in works for me.

amazon, ebay, digikey, or mouser depending on where the deal is after shipping. Generally buying 1 thing amazon or ebay are cheaper.

We didn't add capacitors into the FlowForce PNP harness. It's not needed.

D585 coils 1995 miata and ms3pro pnp
 

Here is a diagram I made for my wiring harness. May help someone. I will make my own build thread before too long. but for now. This is for D585 coils using GM pigtails from junkyard pull, 1994-1995 MX5 MS3Pro pnp

Is anyone running MSD replacements for de LS coils? Like the MSD streetfire ones. I need nee coils for my turbo build. About 300-350hp. Those are easier to get over here in the netherlands then OEM ones i think

Turned out my LS coils i have now are fake.

.

Never mind

Ok, oldish thread but figures it's best to keep all this stuff together rather than have 500 threads clogging up the forum.


Usual thing, will be needing coils soon, etc, etc.

Having read the thread front to back it's pretty clear that most people are using secondhand GM coils, which makes sense if they're readily available.

But have people had much experience with non-GM ones from reputable companies? (specifically NGK U5132)

I mean, I'd assume that the NGK ones would at least meet OEM specs (since they're an OEM supplier, granted not for GM), but yeah, assuming is one thing, experience is another altogether.


I'd happily just grab used GM ones, but it's damn hard to find them here since they were only really fitted to the VE SS Commodore and higher models. None of which ever really end up in the wrecking yards here (plenty of the V6 pov-packs, but very few V8)

Cheers.

I've tested 5 different brands of d585 coils (8 units per brand) on an oscilloscope, and each had significantly less power and more variance coil-to-coil than used OEM. I would have far preferred to find a good new supplier, but we ended up having to do way more work to source, test and refurbish used ones. Granted I haven't tested NGK, but my understanding is that my experience is common across all brands, and that there are just a couple manufacturers in China producing all the new coils available.

PS, we reject about 5% of used coils because they don't match the typical scope profile. Most of those produce a spark, but are just out of spec from the years of abuse.

Damn, that's a shame.

The fact you're refurbishing used coils I presume means that even brand new GM ones aren't meeting spec? (or at least are cost prohibitive)

They are cost prohibitive from reliable providers ($100+ each) and if you buy from Amazon or eBay there's a very high chance you get a faux-EM.

Back 5 or 6 years ago at least that is about what I found. I tried probably half a dozen different off brand new LS coils. I never found any that worked as well as OEM. So now I just go to the local pick and pull and grab coils off trucks. Generally it costs $50 for a set of 4 with wiring harnesses. I haven't had any issues at all with any from the junk yard.

Looks like we should all just move on to IGN-1A smart coils...

I did and made more power and dont even think about the ignition system anymore.

I mean I have 5+ years on my $50 junkyard set of coils. I am still into my LS coil swap for less then 2 IGN-1A coils. I don't think they are a bad coil, and probably better then the LS coils, but we have always been price sensitive on mt.net.


I am also lazy and don't want to make a bracket for IGN-1A coils.

I made some changes over the winter that would have moved the curve "up" but shouldn't have changed the shape of the curve.....other than a stronger ignition system.. The shape of the curve in the upper range is the result of a strong robust spark replacing one that struggled to ignite the mixture at RPM.

that said, properly set up D585s are making tons of power on a lot of setups...but with new coils being "hit or miss" and used coils being just that.....used wear items.....if you a worried about ultimate reliability, reach out to Ben at DIY and get a set of smart coils and never look back.

https://cimg2.ibsrv.net/gimg/www.mia...ba783b8ba5.jpg