MS2 and LS2 coils
 

I'm planning on upgrading to LS2 truck coils.
What kind of changes do I need to make on the MS2?
It's the DIYPNP from Braineack.

I know to set the dwell to 5-5.5.
But since I have and 94 and the LS2 coils don't have a tach output, how do I wire my tach to work?
Are there suppose to be 4 signal wires coming off the MS2 to fire off each coil individually? Reading about the wiring being the same as COP seems like it will make the all the coils fire all the time and not sequential. Of course, I'm probably wrong.


Thanks

https://www.miataturbo.net/showpost....0&postcount=66

read through.

There is a nice set of ls2 coils for sale in the FS section right now. You should check it out and mention that you are installing them on a 94, the seller would probably give you a discount.

Thanks but i alrrady got a set coming from tomskinville auto salvage. They sell packs of 4 for $40.

Thanks brain. For the link.

So I've read the link and the wiring to the coils seems pretty straight forward.
However, I've never taken my ms2 apart before so I don't really understand the modifying part. I bought my ms2 from you so I don't really know what's in it. Has this already been set up or can I send this to you to get done?

Thanks

you can easily just wire the coils for batch without touching the ms2. I'd hav eto see what input/output we are using inside your ms2 to determine if you have enough open to use 2 extra outputs for the 2 extra ignition drivers to go seq. ignition.

To go batch, do I just ground all the grounds to the head, 12v to the blue wire, and 2 coils to brown and 2 coil to brown/yellow? Won't that fire off 2 coils at a time?

What should I do about the tach reading? Can I tap the black/white wire to a wire near the ECU to get a tach reading?

Looks like wiring up for batch is a whole lot easier than sequential. Is there a major advantage to go sequential? I've read smoother idle, but wouldn't I get that from the stronger spark anyway?

That IS batch, it fires 1&4 and 2&3 at the same time, you know, in batches? :) Its how the stock ECU does these things.
I believe my 99/00 gets the signal from the ECU, no idea how Brainy built your PNP, I'm sure he'll chime in here in a sec.
Yes, batch is super easy to wire. Someone more experienced can chime in on the benifits of sequential on an MS2/DIYPNP. I experienced smoother idle when I went from my failboat 99/00 coil to COPs, but YMMV

Ah, now it's starting to make sense. Sorry used to working on american cars with distributers.

I have a 94 so the tach reading comes from the coil unlike the 99.
Unfortunately, the LS coils don't have a tach signal.

You need the tach circuit built on your MS and have it wired to the black/white wire in the main harness. Then you will get a tach signal.

I have the tach circuit built into my ms.
How do i find out where to connect the black/white wire?

Have a look at 2I on your OEM connector.

http://www.boostedmiata.com/gallery2...ne_harness.jpg

Or it could be 2I shielded grey from pin 26 on DB37.

Just got my coils from Tompkinsville Auto Salvage (888-482-0016)
$40 for 4 coils plus bracket
$15 for complete harness, not just a couple inches
$15 shipping

https://www.miataturbo.net/attachmen...ine=1334295993
https://www.miataturbo.net/attachmen...ine=1334295993
https://www.miataturbo.net/attachmen...ine=1334295993

I have a 94 so my harness looks a little different from yours.
But does this mean if I have the tach circuit built in, the tach is already getting the signal from the ms2 and I dont have to run any additional wires?

It's already wired to 4I on your diypnp, so it should already be good. Its the 95.5 model years that have a different spot for it.

Can someone confirm if ALED=ALD and WLED=WLD?
If it is then would this be correct?

https://www.miataturbo.net/attachmen...ine=1334369123

just desolder the red wire to ign2/1H. then just move the wire on ald from 1L to 1H. then do the resistors and jumpers to the db15.


you'll have to move the cooling fan off aled. So jump pao to relay 1 IN, then relay 1 OUT to 1L. youll need to copy the output settings in TS for ALED to the Pa0 output.

My PA0 is currently going to boost control in. Boost control out is going to db15 - pin 15.

What should I do?


Thanks

https://www.miataturbo.net/attachmen...ine=1334447103

What about PT6 or PT7?

So PT6 to to relay 1 IN, then relay 1 OUT to 1L?
Couple of wire moves.
Couple of resistors.
Couple of jumpers.
Sounds doable.

Where should I look to copy the output settings in TS for ALED to the PT6 output?


Thanks

I was planning on using a connector on the engine harness so it's easy to swap back if necessary. A male connector on the engine harness. Female connector coming from the miata coils and a female connector from the LS2 coils.

How far down on the engine harness before the 8 wires from the coils become 5 wires?

I have the entire coil harness for the LS2 coils.
The 12v, signal ground, ground from all the coil plugs combine together to make 3 pins and the signal from each coil makes up the other 4 pins.
I have the male and female side but it looks like getting another oem 7 pin female connector will cost more than getting 2 sets of aftermarket 8 pin Deutsch connectors.

pt6 and pt7 are the seq fuel outputs. you cannot use them.

you still have the mp45? do you need to boost control, because that's the only remaining free output?

Currently still have the supercharger but upgrading everything to get ready for a turbo.
Can i get a separate item for boost control or would i be better off running my coils in batch mode?

MBC still works :)

Text removed.

Oops just read Brains post. I guess that wouldn't work for me either if I had electronic boost control. I agree. Unless you have a programmed switch in the car, manual boost control is just as quick and reliable - with a decent controller. So I guess that means no electronic boost control for me either. Oh well.

Would love to have my cake and eat it too.
Is there a piggyback electronic boost controller?
Switching on the fly would be nice.

So desolder PA0/boost control in, and boost out/db15
Then jump PA0 to relay 1 in and relay out to 1L.
Then all the other resistor, jumpers, etc.
Then program TS. Where should I go in TS to make the changes?

You can always use a standalone EBC.

Or an MBC.

Made a couple of brackets to mount the ls2 truck coils.
It's a tight fit but all 4 coils and bracket slides right in.
This is my first attempt and it works but I think I'll retry and make the coils angle out a bit for more clearance.

Here's a couple of pics:

https://www.miataturbo.net/attachmen...ine=1334817364
https://www.miataturbo.net/attachmen...ine=1334817364

Those coils are THE coils to have.

Lol @ hoppes #9 in the background. You should come visit us in the "Yet Another Gun Thread" ;)

Mounting bracket looks good, I like that it's using the factory holes. Clearance to the firewall will be an issue, I started mocking mine up yesterday. These bastards are big. Do stock plugwires feel like they fit on yours?

The stock wires work, barely. The contacts don't put pressure on the contacts inside the coils. If you were to back a wire out by any amount, there will be a small gap between the wire and coil.

That said: They work for me. I did have some misfire issues when one plug wire started working its way loose, but I changed the routing and won't be having any more problems.

Awesome, thanks Bryce! Can the round contact be "opened up" at all to give a little more tension? I don't even have a set of stock plugwires anymore so I don't have one to look at, sorry for the silly questions. If the stock connectors can be made to fit, I don't see why a set of the big ass Magnecore 8.5 90-00 Miata wires wouldn't fit. Goodwin has them on sale right now for $73

If you are already buying new wires call Magnecore and have them make you custom wires for $20 more that have correct fittings. It is about $90 for a custom set depending on wire length. I can say that my custom wires from FM fit much nicer then my stock wires did. I also had some sort of misfire issue when I was on stock wires.

These brackets clears the firewall. Small enough where I can slide it in as one unit.
I tried a plug from a LT1 motor and they fit.
Take a look at this: http://www.summitracing.com/parts/TAY-46069/
That's if you want to cut one end off your stock wires. Making the wires is quite easy. Just make sure you spray the boot and wire liberally with silicone spray. Makes sliding the boot in easy and it doesn't leave a mess.

I'll be making another bracket that angles coils out a little bit and the 45 degrees boots will work perfect. Problem is the stock wires are not quite long enough to reach one of the coil. I would like to keep the stock boots that goes to the spark plugs to keep the water out. Custom Magnecore wires may be the way to go.

Lars has a good point. I forgot to mention I was talking about the miata magnecore 8.5 mm wires. After taking pictures, they are definitely not ideal, but I think I can make them work well.

Here are the miata magnecor ends:
https://www.miataturbo.net/attachmen...ine=1334868774

And the LS2 coil receptacles:
https://www.miataturbo.net/attachmen...ine=1334868720

The metal contact on the coil is recessed by ~1 cm and is ~2 cm long. Its diameter is probably half that of the contact on the wire ends. The current is probably arcing to get to the wires.

When I have the chance, I will try cutting and bending the wire contacts to a smaller radius.

I looked on magnacor's website. Where did you find the $90 price?
I'm hoping they can make LS2 coil boots on one side and Miata plug boots on the other end.

Stock wire have HEI style/size contacts so it's much bigger than the LT1/LS2 style. With the proper terminal, it clicks and locks into place. You could get a set of miata wires from Magnacor and redo the coil end with new terminals from summitracing. But because of the placement of my coils I need longer wires.

Just wanted to confirm before I fry anything.
I can take the 4 signal ground and 4 other ground wire coming from the coil and ground them all 8 to one point on the the head right?

Call the phone number on Magnecor's website. You have to custom order the wires. The price varies based on the length of the wires. They told me it would take a day or two for them to assemble the wires and get them out to me. Since I used the FM bracket I just ordered the wires that FM already has made for $89.

I have the ground wires grounded to 2 different points on my head. Theoretically you should run the signal ground wires back to the signal ground pins at the MS, then ground the other ones to the block.

Do you know if the black wire from the coil harness is going to chassis or ecu?

I have all the coil grounds going to one point on my head. It is working great.

It was posted on this forum the signal ground is for ion-sensing misfire detection with the OEM ECU.

I know im bringing this back from the dead.

I have the Sequencer ground from all four coils going back to the megasquirt and I have .001 uf caps on the stock miata brown and brown with yellow that are connected to the signal ground. "caps are going from brw and brw yellow to signal ground"

For some reason the car is only firing on cylinder 2 and 3.

1 and 4 are getting 12 volts power and when I hook up my volt meter it reads 12 volts from both signal ground and my head ground. I also get 12 volts out of the signal on all four.

I believe the wiring is correct but it is only firing on 2 and 3. Not sure what I have done wrong.

Does anyone have a detailed wiring diagram?

Currnetly I have

12v to all all the 12v red wires on ls2 coils

Ground going to head from all black ground wires on ls2 coils

Signal Ground going from all brown ls2 coils back to pin 15 on mspnp2 "signal ground"

Brown wire from miata harness going to the signal wire for ls2 coils on 2 and 3

Brown and yellow from miata harness going to the signal wire on ls2 coils for 1 and 4.

I have tried swapping coils and have no luck, 1 and 4 just wont fire.

it does fire 1 and 4 with my stock coils and harness

Thanks for any help.

Do the coils fire in output test mode?

I would like to ask you guys, in the know, a question. Is there a reason why you can't run all 4 ignition circuits (IGN1, IGN2, WLED, and ALED) into the DB15 and from the DB15 out to the appropriate LS2 Coils?