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