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Hi guys. putting toyota coilpacks on my NA, hoping to remove the ignitor completely and drive the tach from the coil packs

i've got a haltech sprint 500 running the whole shebang

going completely sequential on this so don't need the stock coil or ignitor

my understanding is the signal from the coil packs - of which i'll only need to use one, correct? is a little weak to drive the tach in the instrument cluster?

get the tach signal wire from pin 3 of the Toyota coil pack, and then add a resistor along with a 12v ignition source?

The sprint doesn't have tach output? If so use that, it will be more accurate. If not what na do you have? The Wiring changes.

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Yep haltech has a tach out, but its a programmable output and i may have already used it up for boost control - gonna check with those guys tomorrow..

also don't think its got enough juice to run the old style tacho, it's a 90 model

Ok, is be surprised if it can't run the tacho if it can run anything else. The adaptronic certainly can. Using the tach output will keep the tacho accurate in an ignition based rev cut situation.

I also done the tacho from the Toyota coils, which also worked fine but I started with a na8, so different wiring.

There is a guide on how to do it on miata. Net or miata turbo. Have you tried Google?

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Yep have googled and looked at a bunch of diagrams

guess the problem is i dont have enough background theory on how the ignitor works but it looks like it sends the tachno signal to the dash, and the signal coming out of the coils is weaker

have asked the haltech guys will post back when i get a 100% correct solution

Try Pming Plohl. He did it with his and it works. he's using an old haltec as well.

I am using the coils for the tacho - not driving it from the ecu.

its simple,
1)Wire up the coilpacks as per wiring diagram
2)Use the Haltech tach output and slice it into the ignitor (i think its blue/white from memory) tach wire
3) Done.